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Properties of metals, metalloids and nonmetals
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<h2 id="properties">Properties</h2> <h3>Metals</h3> <p class="note">Main article: <a href="/facts/Metal/PT8hNX6R">Metal</a></p> <p>Elemental metals appear lustrous (beneath any <a href="/facts/Patina/IVQsrSMM">patina</a>); form compounds (<a href="/facts/Alloy/I7w7WQWR">alloys</a>) when combined with other elements; tend to lose or share electrons when they react with other substances; and each forms at least one predominantly basic oxide. </p><p>Most metals are silvery looking, high density, relatively soft and easily deformed solids with good <a href="/facts/Electrical_conductivity/akyCKvMy">electrical</a> and <a href="/facts/Thermal_conductivity/qWnSG3nQ">thermal conductivity</a>, <a href="/facts/Atomic_packing_factor/xCLpEPlN">closely packed structures</a>, low <a href="/facts/Ionisation_energy/lezUajfA">ionisation energies</a> and <a href="/facts/Electronegativity/H7Vq7Uah">electronegativities</a>, and are found naturally in combined states. </p><p>Some metals appear coloured (<a href="/facts/Copper/I8PEE8oX">Cu</a>, <a href="/facts/Caesium/dXKN1S5k">Cs</a>, <a href="/facts/Gold/1znknojp">Au</a>), have low <a href="/facts/Density/92p6hh9I">densities</a> (e.g. <a href="/facts/Beryllium/dv295voP">Be</a>, <a href="/facts/Aluminium/7wmR8jYE">Al</a>) or very <a href="/facts/Refractory_metal/WtGXfsVQ">high melting points</a> (e.g. <a href="/facts/Tungsten/WYwbNDYX">W</a>, <a href="/facts/Niobium/3zNI8AKp">Nb</a>), are liquids at or near room temperature (e.g. <a href="/facts/Mercury_(element)/WlxfoHva">Hg</a>, <a href="/facts/Gallium/EucevDs9">Ga</a>), are brittle (e.g. <a href="/facts/Osmium/1TjXD69n">Os</a>, <a href="/facts/Bismuth/75FLjkoX">Bi</a>), not easily machined (e.g. <a href="/facts/Titanium/53ArnDoy">Ti</a>, <a href="/facts/Rhenium/TzyqJYEn">Re</a>), or are noble (hard to <a href="/facts/Corrosion/lIC7H4we">oxidise</a>, e.g. <a href="/facts/Gold/1znknojp">Au</a>, <a href="/facts/Platinum/qJC6lQf7">Pt</a>), or have nonmetallic structures (<a href="/facts/Manganese/j9ELd1TL">Mn</a> and <a href="/facts/Gallium/EucevDs9">Ga</a> are structurally analogous to, respectively, <a href="/facts/White_phosphorus/GarX3byj">white P</a> and <a href="/facts/Iodine/JlfMecMf">I</a>). </p><p>Metals comprise the large majority of the elements, and can be subdivided into several different categories. From left to right in the periodic table, these categories include the highly reactive <a href="/facts/Alkali_metal/IkWbCLk2">alkali metals</a>; the less-reactive <a href="/facts/Alkaline_earth_metals/Ts4U5zIe">alkaline earth metals</a>, <a href="/facts/Lanthanide/rt3XIRCl">lanthanides</a>, and radioactive <a href="/facts/Actinide/kHC4lxJV">actinides</a>; the archetypal <a href="/facts/Transition_metal/0slGWoLQ">transition metals</a>; and the physically and chemically weak <a href="/facts/Post-transition_metal/wjp3aeGn">post-transition metals</a>. Specialized subcategories such as the <a href="/facts/Refractory_metal/WtGXfsVQ">refractory metals</a> and the <a href="/facts/Noble_metal/Pe9EKIvU">noble metals</a> also exist. </p> <h3>Metalloids</h3> <p class="note">Main article: <a href="/facts/Metalloid/uMFVXuTq">Metalloid</a></p> <p>Metalloids are metallic-looking often brittle solids; tend to share electrons when they react with other substances; have weakly acidic or amphoteric oxides; and are usually found naturally in combined states. </p><p>Most are semiconductors, and moderate thermal conductors, and have structures that are more open than those of most metals. </p><p>Some metalloids (<a href="/facts/Arsenic/k1c4f44D">As</a>, <a href="/facts/Antimony/YsA7lVgT">Sb</a>) conduct electricity like metals. </p><p>The metalloids, as the smallest major category of elements, are not subdivided further. </p> <h3>Nonmetals</h3> <p class="note">Main article: <a href="/facts/Nonmetal_(chemistry)/0oejKuzK">Nonmetal (chemistry)</a></p> <p>Nonmetallic elements often have open structures; tend to gain or share electrons when they react with other substances; and do not form distinctly basic oxides. </p><p>Most are gases at room temperature; have relatively low densities; are poor electrical and thermal conductors; have relatively high ionisation energies and electronegativities; form acidic oxides; and are found naturally in uncombined states in large amounts. </p><p>Some nonmetals (<a href="/facts/Black_phosphorus/GarX3byj">black P</a>, <a href="/facts/Sulfur/IK0amTfM">S</a>, and <a href="/facts/Selenium/k975NApC">Se</a>) are brittle solids at room temperature (although each of these also have malleable, pliable or ductile allotropes). </p><p>From left to right in the periodic table, the nonmetals can be divided into the <a href="/facts/Reactive_nonmetal/0oejKuzK">reactive nonmetals</a> and the noble gases. The reactive nonmetals near the metalloids show some incipient metallic character, such as the metallic appearance of graphite, black phosphorus, selenium and iodine. The noble gases are almost completely inert. </p> <h2 id="comparison-of-properties">Comparison of properties</h2> <h3>Overview</h3> <table><tbody><tr><th colspan="108">Number of metalloid properties that resemble metals or nonmetals<ul><li>v</li><li>t</li><li>e</li></ul></th></tr><tr><td colspan="108"><i>(or that are relatively distinct)</i></td></tr><tr><th></th><th></th><th colspan="33"> Resemble metals </th><th colspan="34"> Relatively distinct </th><th colspan="33"> Resemble nonmetals </th></tr><tr><td>Properties compared:</td><td>(37) </td><td colspan="19"> 7 (19%)</td><td colspan="31">25 </td><td colspan="37">(68%)</td><td colspan="13">5 (13%) </td></tr><tr><td>Physical properties</td><td>(21) </td><td colspan="24"> 5 (24%)</td><td colspan="26">14 </td><td colspan="40">(67%)</td><td colspan="10">2 (10%) </td></tr><tr><td> • Form & structure</td><td>(10) </td><td colspan="20"> 2</td><td colspan="30">6 </td><td colspan="30"></td><td colspan="20">2 (20%) </td></tr><tr><td> • Electron-related</td><td>(6) </td><td colspan="17"> 1</td><td colspan="33">5 </td><td colspan="50"></td></tr><tr><td> • Thermodynamics</td><td>(5) </td><td colspan="40"> 2</td><td colspan="10">3 </td><td colspan="50"></td></tr><tr><td>Chemical properties</td><td>(16) </td><td colspan="13"> 2 (13%)</td><td colspan="37">11 </td><td colspan="31">(69%)</td><td colspan="19">3 (19%) </td></tr><tr><td> • Elemental chemistry</td><td>(6) </td><td colspan="50"> 3 </td><td colspan="50">3 (50%) </td></tr><tr><td> • Combined form chemistry</td><td>(6) </td><td colspan="33"> 2</td><td colspan="17">4 </td><td colspan="50"></td></tr><tr><td> • Environmental chemistry</td><td>(4) </td><td colspan="50">4 </td><td colspan="50"></td></tr><tr><td></td><td></td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td></tr></tbody></table> <p>The characteristic properties of elemental metals and nonmetals are quite distinct, as shown in the table below. Metalloids, straddling the <a href="/facts/Dividing_line_between_metals_and_nonmetals/T6P2t8Gc">metal-nonmetal border</a>, are mostly distinct from either, but in a few properties resemble one or the other, as shown in the shading of the metalloid column below and summarized in the small table at the top of this section. </p><p>Authors differ in where they divide metals from nonmetals and in whether they recognize an intermediate <a href="/facts/Metalloid/uMFVXuTq">metalloid</a> category. Some authors count metalloids as nonmetals with weakly nonmetallic properties.<a class="footnote-ref" id="fnref:1" href="#fn:1"><sup>1</sup></a> Others count some of the metalloids as <a href="/facts/Post-transition_metal/wjp3aeGn">post-transition metals</a>.<a class="footnote-ref" id="fnref:2" href="#fn:2"><sup>2</sup></a> </p> <h3>Details</h3> <table><tbody><tr><th colspan="4">Physical and chemical properties<a class="footnote-ref" id="fnref:3" href="#fn:3"><sup>3</sup></a><ul><li>v</li><li>t</li><li>e</li></ul></th></tr><tr><th></th><th>Metals<a class="footnote-ref" id="fnref:4" href="#fn:4"><sup>4</sup></a></th><th>Metalloids</th><th>Nonmetals<a class="footnote-ref" id="fnref:5" href="#fn:5"><sup>5</sup></a></th></tr><tr><td colspan="3">Form and structure</td><td></td></tr><tr><td scope="row">Colour</td><td><ul><li>nearly all are shiny and grey-white</li><li><a href="/facts/Copper/I8PEE8oX">Cu</a>, <a href="/facts/Caesium/dXKN1S5k">Cs</a>, <a href="/facts/Gold/1znknojp">Au</a>: shiny and golden<a class="footnote-ref" id="fnref:6" href="#fn:6"><sup>6</sup></a></li></ul></td><td><ul><li>shiny and grey-white<a class="footnote-ref" id="fnref:7" href="#fn:7"><sup>7</sup></a></li></ul></td><td><ul><li>most are colourless or dull red, yellow, green, or intermediate shades<a class="footnote-ref" id="fnref:8" href="#fn:8"><sup>8</sup></a></li><li><a href="/facts/Carbon/ukrgQexo">C</a>, <a href="/facts/Phosphorus/27xCeIqs">P</a>, <a href="/facts/Selenium/k975NApC">Se</a>, <a href="/facts/Iodine/JlfMecMf">I</a>: shiny and grey-white</li></ul></td></tr><tr><td scope="row"><a href="/facts/Reflectivity/TT4sBwIw">Reflectivity</a></td><td><ul><li>intermediate to typically high<a class="footnote-ref" id="fnref:9" href="#fn:9"><sup>9</sup></a><a class="footnote-ref" id="fnref:10" href="#fn:10"><sup>10</sup></a></li></ul></td><td><ul><li>intermediate<a class="footnote-ref" id="fnref:11" href="#fn:11"><sup>11</sup></a><a class="footnote-ref" id="fnref:12" href="#fn:12"><sup>12</sup></a></li></ul></td><td><ul><li>zero or low (mostly)<a class="footnote-ref" id="fnref:13" href="#fn:13"><sup>13</sup></a> to intermediate<a class="footnote-ref" id="fnref:14" href="#fn:14"><sup>14</sup></a></li></ul></td></tr><tr><td scope="row">Form</td><td><ul><li>almost all solid</li><li><a href="/facts/Rubidium/KDHSe2HM">Rb</a>, <a href="/facts/Caesium/dXKN1S5k">Cs</a>, <a href="/facts/Francium/P3Rz4gDP">Fr</a>, <a href="/facts/Gallium/EucevDs9">Ga</a>, <a href="/facts/Mercury_(element)/WlxfoHva">Hg</a>: liquid at/near <a href="/facts/Standard_temperature_and_pressure/JhJv9KFJ">stp</a><a class="footnote-ref" id="fnref:15" href="#fn:15"><sup>15</sup></a><a class="footnote-ref" id="fnref:16" href="#fn:16"><sup>16</sup></a><a class="footnote-ref" id="fnref:17" href="#fn:17"><sup>17</sup></a></li></ul></td><td><ul><li>all solid<a class="footnote-ref" id="fnref:18" href="#fn:18"><sup>18</sup></a></li></ul></td><td><ul><li>most are gases<a class="footnote-ref" id="fnref:19" href="#fn:19"><sup>19</sup></a></li><li><a href="/facts/Carbon/ukrgQexo">C</a>, <a href="/facts/Phosphorus/27xCeIqs">P</a>, <a href="/facts/Sulfur/IK0amTfM">S</a>, <a href="/facts/Selenium/k975NApC">Se</a>, <a href="/facts/Iodine/JlfMecMf">I</a>: solid; <a href="/facts/Bromine/oLfj3C7D">Br</a>: liquid</li></ul></td></tr><tr><td scope="row"><a href="/facts/Density/92p6hh9I">Density</a></td><td><ul><li>generally high, with some exceptions such as the <a href="/facts/Alkali_metal/IkWbCLk2">alkali metals</a><a class="footnote-ref" id="fnref:20" href="#fn:20"><sup>20</sup></a></li></ul></td><td><ul><li>lower than nearby <a href="/facts/Post-transition_metal/wjp3aeGn">metals</a> but higher than nearby <a href="/facts/Nonmetal_(chemistry)/0oejKuzK">nonmetals</a><a class="footnote-ref" id="fnref:21" href="#fn:21"><sup>21</sup></a></li></ul></td><td><ul><li>often low</li></ul></td></tr><tr><td scope="row">Deformability (as a solid)</td><td><ul><li>most are <a href="/facts/Ductility/SBJsahEk">ductile</a> and malleable</li><li>some are brittle (<a href="/facts/Chromium/6sVk6Uu7">Cr</a>, <a href="/facts/Manganese/j9ELd1TL">Mn</a>, <a href="/facts/Gallium/EucevDs9">Ga</a>, <a href="/facts/Ruthenium/uzCm4ufn">Ru</a>, <a href="/facts/Tungsten/WYwbNDYX">W</a>, <a href="/facts/Osmium/1TjXD69n">Os</a>, <a href="/facts/Bismuth/75FLjkoX">Bi</a>)<a class="footnote-ref" id="fnref:22" href="#fn:22"><sup>22</sup></a><a class="footnote-ref" id="fnref:23" href="#fn:23"><sup>23</sup></a></li></ul></td><td><ul><li>often <a href="/facts/Brittleness/cn27H2vg">brittle</a><a class="footnote-ref" id="fnref:24" href="#fn:24"><sup>24</sup></a></li></ul></td><td><ul><li>often brittle</li><li>some (<a href="/facts/Carbon/ukrgQexo">C</a>, <a href="/facts/Phosphorus/27xCeIqs">P</a>, <a href="/facts/Sulfur/IK0amTfM">S</a>, <a href="/facts/Selenium/k975NApC">Se</a>) have non-brittle forms<a class="footnote-ref" id="fnref:25" href="#fn:25"><sup>25</sup></a></li></ul></td></tr><tr><td scope="row"><a href="/facts/Poisson%2527s_ratio/ppIsaujA">Poisson's ratio</a><a class="footnote-ref" id="fnref:26" href="#fn:26"><sup>26</sup></a></td><td><ul><li>low to high<a class="footnote-ref" id="fnref:27" href="#fn:27"><sup>27</sup></a></li></ul></td><td><ul><li>low to intermediate<a class="footnote-ref" id="fnref:28" href="#fn:28"><sup>28</sup></a></li></ul></td><td><ul><li>low to intermediate<a class="footnote-ref" id="fnref:29" href="#fn:29"><sup>29</sup></a></li></ul></td></tr><tr><td scope="row"><a href="/facts/Crystal_structure/bJ4bCeHd">Crystalline structure</a> at freezing point<a class="footnote-ref" id="fnref:30" href="#fn:30"><sup>30</sup></a></td><td><ul><li>most are <a href="/facts/Hexagonal_crystal_system/sSSok8wo">hexagonal</a> or <a href="/facts/Cubic_crystal_system/92Co7BKM">cubic</a></li><li><a href="/facts/Gallium/EucevDs9">Ga</a>, <a href="/facts/Uranium/n2sGWBzU">U</a>, <a href="/facts/Neptunium/pwp7Yvds">Np</a>: orthorhombic; <a href="/facts/Indium/zRq3stVb">In</a>, <a href="/facts/Tin/obW9mqc3">Sn</a>, <a href="/facts/Protactinium/v87VqTPf">Pa</a>: tetragonal; <a href="/facts/Samarium/09K3kl93">Sm</a>, <a href="/facts/Mercury_(element)/WlxfoHva">Hg</a>, <a href="/facts/Bismuth/75FLjkoX">Bi</a>: rhombohedral; <a href="/facts/Plutonium/4bUw9zH3">Pu</a>: monoclinic</li></ul></td><td><ul><li><a href="/facts/Boron/Pmwgd7Mf">B</a>, <a href="/facts/Arsenic/k1c4f44D">As</a>, <a href="/facts/Antimony/YsA7lVgT">Sb</a>: rhombohedral</li><li><a href="/facts/Silicon/cgWx0hdr">Si</a>, <a href="/facts/Germanium/wtoALHGs">Ge</a>: cubic</li><li><a href="/facts/Tellurium/v7QvfIvS">Te</a>: hexagonal</li></ul></td><td><ul><li><a href="/facts/Hydrogen/BoYHjl0J">H</a>, <a href="/facts/Helium/yRul93TG">He</a>, <a href="/facts/Carbon/ukrgQexo">C</a>, <a href="/facts/Nitrogen/Nf1QpGDz">N</a>, <a href="/facts/Selenium/k975NApC">Se</a>: hexagonal</li><li><a href="/facts/Oxygen/acyn6o8r">O</a>, <a href="/facts/Fluorine/YUV0Fb8m">F</a>, <a href="/facts/Neon/5bF1FwGL">Ne</a>, <a href="/facts/Phosphorus/27xCeIqs">P</a>, <a href="/facts/Argon/QX6NRH6d">Ar</a>, <a href="/facts/Krypton/llkNlCke">Kr</a>, <a href="/facts/Xenon/9E3XR69R">Xe</a>, <a href="/facts/Radon/0V9arWKl">Rn</a>: cubic</li><li><a href="/facts/Sulfur/IK0amTfM">S</a>, <a href="/facts/Chlorine/y27UwYBM">Cl</a>, <a href="/facts/Bromine/oLfj3C7D">Br</a>, <a href="/facts/Iodine/JlfMecMf">I</a>: orthorhombic</li></ul></td></tr><tr><td scope="row"><a href="/facts/Atomic_packing_factor/xCLpEPlN">Packing</a> & <a href="/facts/Coordination_number/mf48hsoX">coordination number</a></td><td><ul><li>close-packed crystal structures<a class="footnote-ref" id="fnref:31" href="#fn:31"><sup>31</sup></a></li><li>high coordination numbers</li></ul></td><td><ul><li>relatively open crystal structures<a class="footnote-ref" id="fnref:32" href="#fn:32"><sup>32</sup></a></li><li>medium coordination numbers<a class="footnote-ref" id="fnref:33" href="#fn:33"><sup>33</sup></a></li></ul></td><td><ul><li>open structures<a class="footnote-ref" id="fnref:34" href="#fn:34"><sup>34</sup></a></li><li>low coordination numbers</li></ul></td></tr><tr><td scope="row"><a href="/facts/Atomic_radius/0mQaIJX9">Atomic radius</a>(calculated)<a class="footnote-ref" id="fnref:35" href="#fn:35"><sup>35</sup></a></td><td><ul><li>intermediate to very large</li><li>112–298 pm, average 187</li></ul></td><td><ul><li>small to intermediate: <a href="/facts/Boron/Pmwgd7Mf">B</a>, <a href="/facts/Silicon/cgWx0hdr">Si</a>, <a href="/facts/Germanium/wtoALHGs">Ge</a>, <a href="/facts/Arsenic/k1c4f44D">As</a>, <a href="/facts/Antimony/YsA7lVgT">Sb</a>, <a href="/facts/Tellurium/v7QvfIvS">Te</a></li><li>87–123 pm, average 115.5 pm</li></ul></td><td><ul><li>very small to intermediate</li><li>31–120 pm, average 76.4 pm</li></ul></td></tr><tr><td scope="row"><a href="/facts/Allotropy/2WUdHWxg">Allotropes</a><a class="footnote-ref" id="fnref:36" href="#fn:36"><sup>36</sup></a><a class="footnote-ref" id="fnref:37" href="#fn:37"><sup>37</sup></a></td><td><ul><li>around half form allotropes</li><li>one (<a href="/facts/Tin/obW9mqc3">Sn</a>) has a metalloid-like allotrope (<a href="/facts/Tin_pest/m94dHmJh">grey Sn</a>, which forms below 13.2 °C<a class="footnote-ref" id="fnref:38" href="#fn:38"><sup>38</sup></a>)</li></ul></td><td><ul><li>all or nearly all form allotropes</li><li>some (e.g. <a href="/facts/Allotropes_of_boron/fzvC5bye">red B</a>, <a href="/facts/Arsenic/k1c4f44D">yellow As</a>) are more nonmetallic in nature</li></ul></td><td><ul><li>some form allotropes</li><li>some (e.g. <a href="/facts/Graphite/sSf3KMXr">graphitic C</a>, <a href="/facts/Allotropes_of_phosphorus/GarX3byj">black P</a>, <a href="/facts/Selenium/k975NApC">grey Se</a>) are more metalloidal or metallic in nature</li></ul></td></tr><tr><td colspan="4">Electron-related</td></tr><tr><td scope="row"><a href="/facts/Block_(periodic_table)/BbzD5jUU">Periodic table block</a></td><td><ul><li><a href="/facts/S-block/BbzD5jUU">s</a>, <a href="/facts/P-block/BbzD5jUU">p</a>, <a href="/facts/D-block/BbzD5jUU">d</a>, <a href="/facts/F-block/BbzD5jUU">f</a><a class="footnote-ref" id="fnref:39" href="#fn:39"><sup>39</sup></a></li></ul></td><td><ul><li>p<a class="footnote-ref" id="fnref:40" href="#fn:40"><sup>40</sup></a></li></ul></td><td><ul><li>s, p<a class="footnote-ref" id="fnref:41" href="#fn:41"><sup>41</sup></a></li></ul></td></tr><tr><td scope="row">Outer <i>s</i> and <i>p</i> electrons</td><td><ul><li>few in number (1–3)</li><li>except 0 (<a href="/facts/Palladium/AXMwDFxs">Pd</a>); 4 (<a href="/facts/Tin/obW9mqc3">Sn</a>, <a href="/facts/Lead/EYljasJN">Pb</a>, <a href="/facts/Flerovium/Aa7uGMuG">Fl</a>); 5 (<a href="/facts/Bismuth/75FLjkoX">Bi</a>); 6 (<a href="/facts/Polonium/G4rzsyjP">Po</a>)</li></ul></td><td><ul><li>medium number (3–7)</li></ul></td><td><ul><li>high number (4–8)</li><li>except 1 (<a href="/facts/Hydrogen/BoYHjl0J">H</a>); 2 (<a href="/facts/Helium/yRul93TG">He</a>)</li></ul></td></tr><tr><td scope="row"><a href="/facts/Electronic_band_structure/W5o7oE2R">Electron bands</a>: (<a href="/facts/Valence_band/2NUALlHJ">valence</a>, <a href="/facts/Conduction_band/2NUALlHJ">conduction</a>)</td><td><ul><li>nearly all have substantial band overlap</li><li><a href="/facts/Bismuth/75FLjkoX">Bi</a>: has slight band overlap (<a href="/facts/Semimetal/ELtXVlI5">semimetal</a>)</li></ul></td><td><ul><li>most have narrow band gap (<a href="/facts/Semiconductor/zFf3mGTE">semiconductors</a>)</li><li><a href="/facts/Arsenic/k1c4f44D">As</a>, <a href="/facts/Antimony/YsA7lVgT">Sb</a> are semimetals</li></ul></td><td><ul><li>most have wide band gap (<a href="/facts/Insulator_(electricity)/SfSXkrh5">insulators</a>)</li><li><a href="/facts/Carbon/ukrgQexo">C</a> (<a href="/facts/Graphite/sSf3KMXr">graphite</a>): a semimetal</li><li><a href="/facts/Phosphorus/27xCeIqs">P</a> (<a href="/facts/Phosphorus/27xCeIqs">black</a>), <a href="/facts/Selenium/k975NApC">Se</a>, <a href="/facts/Iodine/JlfMecMf">I</a>: semiconductors</li></ul></td></tr><tr><td scope="row"><a href="/facts/Electron/L0KBo5cW">Electron</a> behaviour</td><td><ul><li>"free" electrons (facilitating electrical and thermal conductivity)</li></ul></td><td><ul><li>valence electrons less freely delocalized; considerable covalent bonding present<a class="footnote-ref" id="fnref:42" href="#fn:42"><sup>42</sup></a></li><li>have Goldhammer-Herzfeld criterion<a class="footnote-ref" id="fnref:43" href="#fn:43"><sup>43</sup></a> ratios straddling unity<a class="footnote-ref" id="fnref:44" href="#fn:44"><sup>44</sup></a><a class="footnote-ref" id="fnref:45" href="#fn:45"><sup>45</sup></a></li></ul></td><td><ul><li>no, few, or directionally confined "free" electrons (generally hampering electrical and thermal conductivity)</li></ul></td></tr><tr><td scope="row"><a href="/facts/Electrical_conductivity/akyCKvMy">Electrical conductivity</a></td><td><ul><li>good to high<a class="footnote-ref" id="fnref:46" href="#fn:46"><sup>46</sup></a></li></ul></td><td><ul><li>intermediate<a class="footnote-ref" id="fnref:47" href="#fn:47"><sup>47</sup></a> to good<a class="footnote-ref" id="fnref:48" href="#fn:48"><sup>48</sup></a></li></ul></td><td><ul><li>poor to good<a class="footnote-ref" id="fnref:49" href="#fn:49"><sup>49</sup></a></li></ul></td></tr><tr><td scope="row">... as a liquid<a class="footnote-ref" id="fnref:50" href="#fn:50"><sup>50</sup></a></td><td><ul><li>falls gradually as temperature rises<a class="footnote-ref" id="fnref:51" href="#fn:51"><sup>51</sup></a></li></ul></td><td><ul><li>most behave like metals<a class="footnote-ref" id="fnref:52" href="#fn:52"><sup>52</sup></a><a class="footnote-ref" id="fnref:53" href="#fn:53"><sup>53</sup></a></li></ul></td><td><ul><li>increases as temperature rises</li></ul></td></tr><tr><td colspan="4">Thermodynamics</td></tr><tr><td scope="row"><a href="/facts/Thermal_conductivity/qWnSG3nQ">Thermal conductivity</a></td><td><ul><li>medium to high<a class="footnote-ref" id="fnref:54" href="#fn:54"><sup>54</sup></a></li></ul></td><td><ul><li>mostly intermediate;<a class="footnote-ref" id="fnref:55" href="#fn:55"><sup>55</sup></a><a class="footnote-ref" id="fnref:56" href="#fn:56"><sup>56</sup></a> <a href="/facts/Silicon/cgWx0hdr">Si</a> is high</li></ul></td><td><ul><li>almost negligible<a class="footnote-ref" id="fnref:57" href="#fn:57"><sup>57</sup></a> to very high<a class="footnote-ref" id="fnref:58" href="#fn:58"><sup>58</sup></a></li></ul></td></tr><tr><td scope="row"><a href="/facts/Temperature_coefficient/Ayc1aNdm">Temperature coefficient of resistance</a><a class="footnote-ref" id="fnref:59" href="#fn:59"><sup>59</sup></a></td><td><ul><li>nearly all positive (<a href="/facts/Plutonium/4bUw9zH3">Pu</a> is negative)<a class="footnote-ref" id="fnref:60" href="#fn:60"><sup>60</sup></a></li></ul></td><td><ul><li>negative (<a href="/facts/Boron/Pmwgd7Mf">B</a>, <a href="/facts/Silicon/cgWx0hdr">Si</a>, <a href="/facts/Germanium/wtoALHGs">Ge</a>, <a href="/facts/Tellurium/v7QvfIvS">Te</a>)<a class="footnote-ref" id="fnref:61" href="#fn:61"><sup>61</sup></a> or positive (<a href="/facts/Arsenic/k1c4f44D">As</a>, <a href="/facts/Antimony/YsA7lVgT">Sb</a>)<a class="footnote-ref" id="fnref:62" href="#fn:62"><sup>62</sup></a></li></ul></td><td><ul><li>nearly all negative (<a href="/facts/Carbon/ukrgQexo">C</a>, as <a href="/facts/Graphite/sSf3KMXr">graphite</a>, is positive in the direction of its planes)<a class="footnote-ref" id="fnref:63" href="#fn:63"><sup>63</sup></a><a class="footnote-ref" id="fnref:64" href="#fn:64"><sup>64</sup></a></li></ul></td></tr><tr><td scope="row">Melting point</td><td><ul><li>mostly high</li></ul></td><td><ul><li>mostly high</li></ul></td><td><ul><li>mostly low</li></ul></td></tr><tr><td scope="row">Melting behaviour</td><td><ul><li>volume generally expands<a class="footnote-ref" id="fnref:65" href="#fn:65"><sup>65</sup></a></li></ul></td><td><ul><li>some contract, unlike (most)<a class="footnote-ref" id="fnref:66" href="#fn:66"><sup>66</sup></a> metals<a class="footnote-ref" id="fnref:67" href="#fn:67"><sup>67</sup></a></li></ul></td><td><ul><li>volume generally expands<a class="footnote-ref" id="fnref:68" href="#fn:68"><sup>68</sup></a></li></ul></td></tr><tr><td scope="row"><a href="/facts/Enthalpy_of_fusion/eLJIURcp">Enthalpy of fusion</a></td><td><ul><li>low to high</li></ul></td><td><ul><li>intermediate to very high</li></ul></td><td><ul><li>very low to low (except <a href="/facts/Carbon/ukrgQexo">C</a>: very high)</li></ul></td></tr><tr><td colspan="4">Elemental chemistry</td></tr><tr><td scope="row">Overall behaviour</td><td><ul><li>metallic</li></ul></td><td><ul><li>nonmetallic<a class="footnote-ref" id="fnref:69" href="#fn:69"><sup>69</sup></a></li></ul></td><td><ul><li>nonmetallic</li></ul></td></tr><tr><td scope="row"><a href="/facts/Ion/3bePpDna">Ion</a> formation</td><td><ul><li>tend to form <a href="/facts/Cation/wrbwhF3z">cations</a></li></ul></td><td><ul><li>some tendency to form <a href="/facts/Anion/wrbwhF3z">anions</a> in water<a class="footnote-ref" id="fnref:70" href="#fn:70"><sup>70</sup></a></li><li>solution chemistry dominated by formation and reactions of <a href="/facts/Oxyanion/0GuWXr6D">oxyanions</a><a class="footnote-ref" id="fnref:71" href="#fn:71"><sup>71</sup></a><a class="footnote-ref" id="fnref:72" href="#fn:72"><sup>72</sup></a></li></ul></td><td><ul><li>tend to form anions</li></ul></td></tr><tr><td scope="row"><a href="/facts/Chemical_bond/ArNUMnIB">Bonds</a></td><td><ul><li>seldom form covalent compounds</li></ul></td><td><ul><li>form <a href="/facts/Salt_(chemistry)/lsSKwGpn">salts</a> as well as <a href="/facts/Covalent_bond/EzMLf3Pz">covalent</a> compounds<a class="footnote-ref" id="fnref:73" href="#fn:73"><sup>73</sup></a></li></ul></td><td><ul><li>form many covalent compounds</li></ul></td></tr><tr><td scope="row"><a href="/facts/Oxidation_number/W53W6s6V">Oxidation number</a></td><td><ul><li>nearly always positive</li></ul></td><td><ul><li>positive or negative<a class="footnote-ref" id="fnref:74" href="#fn:74"><sup>74</sup></a></li></ul></td><td><ul><li>positive or negative</li></ul></td></tr><tr><td scope="row"><a href="/facts/Ionization_energy/lezUajfA">Ionization energy</a></td><td><ul><li>relatively low</li></ul></td><td><ul><li>intermediate<a class="footnote-ref" id="fnref:75" href="#fn:75"><sup>75</sup></a><a class="footnote-ref" id="fnref:76" href="#fn:76"><sup>76</sup></a></li></ul></td><td><ul><li>high</li></ul></td></tr><tr><td scope="row"><a href="/facts/Electronegativity/H7Vq7Uah">Electronegativity</a></td><td><ul><li>usually low</li></ul></td><td><ul><li>close to 2,<a class="footnote-ref" id="fnref:77" href="#fn:77"><sup>77</sup></a> i.e., 1.9–2.2<a class="footnote-ref" id="fnref:78" href="#fn:78"><sup>78</sup></a><a class="footnote-ref" id="fnref:79" href="#fn:79"><sup>79</sup></a></li></ul></td><td><ul><li>high</li></ul></td></tr><tr><td colspan="4">Combined form chemistry</td></tr><tr><td scope="row">With metals</td><td><ul><li>form <a href="/facts/Alloy/I7w7WQWR">alloys</a></li></ul></td><td><ul><li>can form alloys<a class="footnote-ref" id="fnref:80" href="#fn:80"><sup>80</sup></a><a class="footnote-ref" id="fnref:81" href="#fn:81"><sup>81</sup></a><a class="footnote-ref" id="fnref:82" href="#fn:82"><sup>82</sup></a></li></ul></td><td><ul><li>form <a href="/facts/Ionic_compounds/jB9nMfrE">ionic</a> or <a href="/facts/Interstitial_compound/2JH71t2U">interstitial</a> compounds</li></ul></td></tr><tr><td scope="row">With carbon</td><td><ul><li><a href="/facts/Carbide/xfCMTjYJ">carbides</a> and <a href="/facts/Organometallic_compound/bhqFz2P0">organometallic compounds</a></li></ul></td><td><ul><li>same as metals</li></ul></td><td><ul><li>carbon-nonmetal (e.g. <a href="/facts/Carbon_dioxide/xGzpppEp">CO2</a>, <a href="/facts/Carbon_disulfide/b04Tadmy">CS2</a>)<a class="footnote-ref" id="fnref:83" href="#fn:83"><sup>83</sup></a> or <a href="/facts/Organic_compound/gqCNaN45">organic</a> (e.g. <a href="/facts/Methane/kBHneYnh">CH4</a>, <a href="/facts/Sucrose/7y1ke94L">C6H12O6)</a> compounds</li></ul></td></tr><tr><td scope="row">With hydrogen (<a href="/facts/Hydride/v2rlBGMg">hydrides</a>)</td><td><ul><li>ionic, with <a href="/facts/Alkali_metal/IkWbCLk2">alkali metals</a>, <a href="/facts/Alkaline_earth_metal/Ts4U5zIe">alkaline earth metals</a></li><li>metallic, with <a href="/facts/Transition_metal/0slGWoLQ">transition metals</a></li><li>covalent, with <a href="/facts/Post-transition_metal/wjp3aeGn">post-transition metals</a></li></ul></td><td><ul><li>covalent, volatile hydrides<a class="footnote-ref" id="fnref:84" href="#fn:84"><sup>84</sup></a></li></ul></td><td><ul><li>covalent, gaseous or liquid hydrides</li></ul></td></tr><tr><td scope="row">With oxygen (<a href="/facts/Oxide/DXtoVe1C">oxides</a>)</td><td><ul><li>nearly all solid (<a href="/facts/Manganese_heptoxide/L2vcJBJH">Mn2O7</a> is a liquid)</li><li>very few glass formers<a class="footnote-ref" id="fnref:85" href="#fn:85"><sup>85</sup></a></li><li>lower oxides: <a href="/facts/Ionic_compound/jB9nMfrE">ionic</a> and <a href="/facts/Base_(chemistry)/M9wA7qeM">basic</a></li><li>higher oxides: more <a href="/facts/Covalent_bond/EzMLf3Pz">covalent</a>, <a href="/facts/Acid/FySU18n1">acidic</a></li></ul></td><td><ul><li>solid</li><li><a href="/facts/Glass_formation/dl89jNr1">glass formers</a> (<a href="/facts/Boron/Pmwgd7Mf">B</a>, <a href="/facts/Silicon/cgWx0hdr">Si</a>, <a href="/facts/Germanium/wtoALHGs">Ge</a>, <a href="/facts/Arsenic/k1c4f44D">As</a>, <a href="/facts/Antimony/YsA7lVgT">Sb</a>, <a href="/facts/Tellurium/v7QvfIvS">Te</a>)<a class="footnote-ref" id="fnref:86" href="#fn:86"><sup>86</sup></a></li><li>polymeric in structure;<a class="footnote-ref" id="fnref:87" href="#fn:87"><sup>87</sup></a> tend to be <a href="/facts/Amphoteric/2UrXEsyl">amphoteric</a> or weakly acidic<a class="footnote-ref" id="fnref:88" href="#fn:88"><sup>88</sup></a><a class="footnote-ref" id="fnref:89" href="#fn:89"><sup>89</sup></a></li></ul></td><td><ul><li>solid, liquid or gaseous</li><li>few <a href="/facts/Glass_formation/dl89jNr1">glass formers</a> (<a href="/facts/Phosphorus/27xCeIqs">P</a>, <a href="/facts/Sulfur/IK0amTfM">S</a>, <a href="/facts/Selenium/k975NApC">Se</a>)<a class="footnote-ref" id="fnref:90" href="#fn:90"><sup>90</sup></a></li><li>covalent, acidic</li></ul></td></tr><tr><td scope="row">With sulfur (<a href="/facts/Sulfate/yuWVxsUf">sulfates</a>)</td><td><ul><li>do form<a class="footnote-ref" id="fnref:91" href="#fn:91"><sup>91</sup></a><a class="footnote-ref" id="fnref:92" href="#fn:92"><sup>92</sup></a></li></ul></td><td><ul><li>most form<a class="footnote-ref" id="fnref:93" href="#fn:93"><sup>93</sup></a></li></ul></td><td><ul><li>some form<a class="footnote-ref" id="fnref:94" href="#fn:94"><sup>94</sup></a></li></ul></td></tr><tr><td scope="row">With halogens (<a href="/facts/Halide/ujYu8kGD">halides</a>, esp. <a href="/facts/Chloride/m9NUaUDR">chlorides</a>) (see also<a class="footnote-ref" id="fnref:95" href="#fn:95"><sup>95</sup></a>)</td><td><ul><li>typically ionic, involatile</li><li>generally insoluble in organic solvents</li><li>mostly water-soluble (not <a href="/facts/Hydrolysis/JTvwIHPs">hydrolysed</a>)</li><li>more covalent, <a href="/facts/Volatility_(chemistry)/90r3ep6w">volatile</a>, and susceptible to hydrolysis<a class="footnote-ref" id="fnref:96" href="#fn:96"><sup>96</sup></a> and organic solvents with higher halogens and weaker metals<a class="footnote-ref" id="fnref:97" href="#fn:97"><sup>97</sup></a><a class="footnote-ref" id="fnref:98" href="#fn:98"><sup>98</sup></a></li></ul></td><td><ul><li>covalent, volatile<a class="footnote-ref" id="fnref:99" href="#fn:99"><sup>99</sup></a></li><li>usually dissolve in organic solvents<a class="footnote-ref" id="fnref:100" href="#fn:100"><sup>100</sup></a></li><li>partly or completely hydrolysed<a class="footnote-ref" id="fnref:101" href="#fn:101"><sup>101</sup></a></li><li>some reversibly hydrolysed<a class="footnote-ref" id="fnref:102" href="#fn:102"><sup>102</sup></a></li></ul></td><td><ul><li>covalent, volatile</li><li>usually dissolve in organic solvents</li><li>generally completely or extensively hydrolyzed</li><li>not always susceptible to hydrolysis if parent nonmetal at maximum covalency for <a href="/facts/Period_(periodic_table)/WpGUFh5V">period</a> e.g. CF4, SF6 (then nil reaction)<a class="footnote-ref" id="fnref:103" href="#fn:103"><sup>103</sup></a></li></ul></td></tr><tr><td colspan="4">Environmental chemistry</td></tr><tr><td scope="row"><a href="/facts/Mole_(chemistry)/kCMFwCc0">Molar</a> composition of Earth's <a href="/facts/Biosphere/P1ltA4sb">ecosphere</a><a class="footnote-ref" id="fnref:104" href="#fn:104"><sup>104</sup></a></td><td><ul><li>about 14%, mostly Al, Na, Mg, Ca, Fe, K</li></ul></td><td><ul><li>about 17%, mostly Si</li></ul></td><td><ul><li>about 69%, mostly O, H</li></ul></td></tr><tr><td scope="row">Primary form <a href="/facts/Abundance_of_the_chemical_elements/CE9WehBl">on Earth</a></td><td><ul><li>most occur in combined states, as <a href="/facts/Carbonate/FES1QHkN">carbonates</a>, <a href="/facts/Silicate/7NdthSRM">silicates</a>, <a href="/facts/Phosphate/FDGVCxUG">phosphates</a>, <a href="/facts/Oxide/DXtoVe1C">oxides</a>, <a href="/facts/Sulfide/d8YMjLeu">sulfides</a>, or <a href="/facts/Halide/ujYu8kGD">halides</a></li><li>some (e.g. <a href="/facts/Gold/1znknojp">Au</a>, <a href="/facts/Copper/I8PEE8oX">Cu</a>, <a href="/facts/Silver/xXe41BGg">Ag</a>, <a href="/facts/Platinum/qJC6lQf7">Pt</a>) occur in free or uncombined states<a class="footnote-ref" id="fnref:105" href="#fn:105"><sup>105</sup></a></li></ul></td><td><ul><li>all occur in combined states, as <a href="/facts/Borate/5XwkBTv1">borates</a>, silicates, sulfides, or <a href="/facts/Telluride_(chemistry)/r8gVazKR">tellurides</a></li></ul></td><td><ul><li>elemental <a href="/facts/Carbon/ukrgQexo">C</a>, <a href="/facts/Nitrogen/Nf1QpGDz">N</a>, <a href="/facts/Oxygen/acyn6o8r">O</a>, <a href="/facts/Sulfur/IK0amTfM">S</a>, <a href="/facts/Noble_gas/j0yHMEAE">noble gases</a> are plentiful</li><li><a href="/facts/Hydrogen/BoYHjl0J">H</a>,<a class="footnote-ref" id="fnref:106" href="#fn:106"><sup>106</sup></a> <a href="/facts/Fluorine/YUV0Fb8m">F</a><a class="footnote-ref" id="fnref:107" href="#fn:107"><sup>107</sup></a>, <a href="/facts/Selenium/k975NApC">Se</a> occur primarily in compounds</li><li><a href="/facts/Phosphorus/27xCeIqs">P</a>, <a href="/facts/Chlorine/y27UwYBM">Cl</a>, <a href="/facts/Bromine/oLfj3C7D">Br</a>, <a href="/facts/Iodine/JlfMecMf">I</a> occur only in compounds, as phosphates, oxides, <a href="/facts/Selenide/vA9Ls4xH">selenides</a> or halides</li></ul></td></tr><tr><td scope="row"><a href="/facts/Dietary_element/ACv8EG7f">Required by mammals</a></td><td><ul><li>large amounts needed: <a href="/facts/Sodium/eYuSPu2V">Na</a>, <a href="/facts/Magnesium/XyIhd2FG">Mg</a>, <a href="/facts/Potassium/FWPwS7Rj">K</a>, <a href="/facts/Calcium/hf252CC0">Ca</a></li><li>trace amounts needed of some others</li></ul></td><td><ul><li>trace amounts needed: <a href="/facts/Boron/Pmwgd7Mf">B</a>, <a href="/facts/Silicon/cgWx0hdr">Si</a>, <a href="/facts/Arsenic/k1c4f44D">As</a></li></ul></td><td><ul><li>large amounts needed: <a href="/facts/Hydrogen/BoYHjl0J">H</a>, <a href="/facts/Carbon/ukrgQexo">C</a>, <a href="/facts/Nitrogen/Nf1QpGDz">N</a>, <a href="/facts/Oxygen/acyn6o8r">O</a>, <a href="/facts/Phosphorus/27xCeIqs">P</a>, <a href="/facts/Sulfur/IK0amTfM">S</a>, <a href="/facts/Chlorine/y27UwYBM">Cl</a></li><li>trace amounts needed: <a href="/facts/Selenium/k975NApC">Se</a>, <a href="/facts/Bromine/oLfj3C7D">Br</a>, <a href="/facts/Iodine/JlfMecMf">I</a>, possibly <a href="/facts/Fluorine/YUV0Fb8m">F</a></li><li>only noble gases not needed</li></ul></td></tr><tr><td scope="row"><a href="/facts/Composition_of_the_human_body/bbPXIH0x">Composition of the human body</a>, by weight</td><td><ul><li>about 1.5% <a href="/facts/Calcium/hf252CC0">Ca</a></li><li>traces of most others through 92<a href="/facts/Uranium/n2sGWBzU">U</a></li></ul></td><td><ul><li>trace amounts of <a href="/facts/Boron/Pmwgd7Mf">B</a>, <a href="/facts/Silicon/cgWx0hdr">Si</a>, <a href="/facts/Germanium/wtoALHGs">Ge</a>, <a href="/facts/Arsenic/k1c4f44D">As</a>, <a href="/facts/Antimony/YsA7lVgT">Sb</a>, <a href="/facts/Tellurium/v7QvfIvS">Te</a></li></ul></td><td><ul><li>about 97% <a href="/facts/Oxygen/acyn6o8r">O</a>, <a href="/facts/Carbon/ukrgQexo">C</a>, <a href="/facts/Hydrogen/BoYHjl0J">H</a>, <a href="/facts/Nitrogen/Nf1QpGDz">N</a>, <a href="/facts/Phosphorus/27xCeIqs">P</a></li><li>others detectable except noble gases</li></ul></td></tr></tbody></table> <h2 id="anomalous-properties">Anomalous properties</h2> <p>Within each category, elements can be found with one or two properties very different from the expected norm, or that are otherwise notable. </p> <h3>Metals</h3> <p><a href="/facts/Sodium/eYuSPu2V">Sodium</a>, <a href="/facts/Potassium/FWPwS7Rj">potassium</a>, <a href="/facts/Rubidium/KDHSe2HM">rubidium</a>, <a href="/facts/Caesium/dXKN1S5k">caesium</a>, <a href="/facts/Barium/IkL09XHQ">barium</a>, <a href="/facts/Platinum/qJC6lQf7">platinum</a>, <a href="/facts/Gold/1znknojp">gold</a> </p> <ul><li>The common notions that "alkali metal ions (group 1A) always have a +1 charge"<a class="footnote-ref" id="fnref:108" href="#fn:108"><sup>108</sup></a> and that "transition elements do not form anions"<a class="footnote-ref" id="fnref:109" href="#fn:109"><sup>109</sup></a> are <a href="/facts/Textbook/9sunkH2y">textbook</a> errors. The synthesis of a crystalline salt of the sodium anion Na− was reported in 1974. Since then further compounds ("<a href="/facts/Alkalide/6lw9cCFv">alkalides</a>") containing anions of all other <a href="/facts/Alkali_metal/IkWbCLk2">alkali metals</a> except <a href="/facts/Lithium/7vXX6BWA">Li</a> and <a href="/facts/Francium/P3Rz4gDP">Fr</a>, as well as that of <a href="/facts/Barium/IkL09XHQ">Ba</a>, have been prepared. In 1943, Sommer reported the preparation of the yellow transparent compound <a href="/facts/Caesium_auride/J5sIPNNy">CsAu</a>. This was subsequently shown to consist of caesium cations (Cs+) and auride anions (Au−) although it was some years before this conclusion was accepted. Several other aurides (KAu, RbAu) have since been synthesized, as well as the red transparent compound Cs2Pt which was found to contain Cs+ and Pt2− ions.<a class="footnote-ref" id="fnref:110" href="#fn:110"><sup>110</sup></a></li></ul> <p><a href="/facts/Manganese/j9ELd1TL">Manganese</a> </p> <ul><li>Well-behaved metals have crystal structures featuring <a href="/facts/Unit_cell/znygJqdx">unit cells</a> with up to four atoms. Manganese has a complex crystal structure with a 58-atom unit cell, effectively four different atomic radii, and four different <a href="/facts/Coordination_number/mf48hsoX">coordination numbers</a> (10, 11, 12 and 16). It has been described as resembling "a quaternary <a href="/facts/Intermetallic_compound/nnzksayl">intermetallic compound</a> with four Mn atom types bonding as if they were different elements."<a class="footnote-ref" id="fnref:111" href="#fn:111"><sup>111</sup></a> The half-filled <i>3d</i> shell of manganese appears to be the cause of the complexity. This confers a large <a href="/facts/Magnetic_moment/VpAQKJtr">magnetic moment</a> on each atom. Below 727 °C, a unit cell of 58 spatially diverse atoms represents the energetically lowest way of achieving a zero net magnetic moment.<a class="footnote-ref" id="fnref:112" href="#fn:112"><sup>112</sup></a> The crystal structure of manganese makes it a hard and brittle metal, with low electrical and thermal conductivity. At higher temperatures "greater lattice vibrations nullify magnetic effects"<a class="footnote-ref" id="fnref:113" href="#fn:113"><sup>113</sup></a> and manganese adopts less-complex structures.<a class="footnote-ref" id="fnref:114" href="#fn:114"><sup>114</sup></a></li></ul> <p><a href="/facts/Iron/QK1JYy8E">Iron</a>, <a href="/facts/Cobalt/gqhScEw4">cobalt</a>, <a href="/facts/Nickel/KwMCHYRP">nickel</a>, <a href="/facts/Gadolinium/eLYUeScu">gadolinium</a>, <a href="/facts/Terbium/ICF3PMED">terbium</a>, <a href="/facts/Dysprosium/eMev6zGS">dysprosium</a>, <a href="/facts/Holmium/C73kJVtp">holmium</a>, <a href="/facts/Erbium/XEJlgJcx">erbium</a>, <a href="/facts/Thulium/G2905xhd">thulium</a> </p> <ul><li>The only elements strongly attracted to magnets are iron, cobalt, and nickel at room temperature, gadolinium just below, and terbium, dysprosium, holmium, erbium, and thulium at ultra-cold temperatures (below −54 °C, −185 °C, −254 °C, −254 °C, and −241 °C respectively).<a class="footnote-ref" id="fnref:115" href="#fn:115"><sup>115</sup></a></li></ul> <p><a href="/facts/Iridium/TFQutoj1">Iridium</a> </p> <ul><li>The only element encountered with an oxidation state of +9 is iridium, in the [IrO4]+ cation. Other than this, the highest known oxidation state is +8, in <a href="/facts/Ruthenium/uzCm4ufn">Ru</a>, <a href="/facts/Xenon/9E3XR69R">Xe</a>, <a href="/facts/Osmium/1TjXD69n">Os</a>, <a href="/facts/Iridium/TFQutoj1">Ir</a>, and <a href="/facts/Hassium/t0bgGzwt">Hs</a>.<a class="footnote-ref" id="fnref:116" href="#fn:116"><sup>116</sup></a></li></ul> <p><a href="/facts/Gold/1znknojp">Gold</a> </p> <ul><li>The <a href="/facts/Malleable/SBJsahEk">malleability</a> of gold is extraordinary: a fist-sized lump can be hammered and separated into one million paperback-sized sheets, each 10 <a href="/facts/Nanometer/a98sjHyu">nm</a> thick, 1600 times thinner than regular kitchen aluminium foil (0.016 mm thick).</li></ul> <p><a href="/facts/Mercury_(element)/WlxfoHva">Mercury</a> </p> <ol><li>Bricks and bowling balls will float on the surface of mercury thanks to it having a density 13.5 times that of water. Equally, a solid mercury bowling ball would weigh around 50 pounds and, if it could be kept cold enough, would float on the surface of liquid <a href="/facts/Gold/1znknojp">gold</a>.</li> <li>The only metal having an ionisation energy higher than some nonmetals (<a href="/facts/Sulfur/IK0amTfM">sulfur</a> and <a href="/facts/Selenium/k975NApC">selenium</a>) is mercury.</li> <li>Mercury and its compounds have a reputation for toxicity but on a scale of 1 to 10, <a href="/facts/Dimethylmercury/ettgPTS7">dimethylmercury</a> ((CH3)2Hg) (abbr. DMM), a volatile colourless liquid, has been described as a 15. It is so dangerous that scientists have been encouraged to use less-toxic mercury compounds wherever possible. In 1997, <a href="/facts/Karen_Wetterhahn/cSpFzRrG">Karen Wetterhahn</a>, a professor of chemistry specialising in toxic metal exposure, died of mercury poisoning ten months after a few drops of DMM landed on her "protective" latex gloves. Although Wetterhahn had been following the then-published procedures for handling this compound, it passed through her gloves and skin within seconds. It is now known that DMM is exceptionally permeable to (ordinary) gloves, skin, and tissues. And its toxicity is such that less than one-tenth of a ml applied to the skin will be seriously toxic.<a class="footnote-ref" id="fnref:117" href="#fn:117"><sup>117</sup></a></li></ol> <p><a href="/facts/Lead/EYljasJN">Lead</a> </p> <ul><li>The expression, to "go down like a lead balloon" is anchored in the common view of lead as a dense, heavy metal—being nearly as dense as mercury. However, it is possible to construct a balloon made of lead foil, filled with a <a href="/facts/Helium/yRul93TG">helium</a> and air mixture, which will float and be buoyant enough to carry a small load.</li></ul> <p><a href="/facts/Bismuth/75FLjkoX">Bismuth</a> </p> <ul><li>Bismuth has the longest <a href="/facts/Half-life/kGVH8BAB">half-life</a> of any naturally occurring element; its only <a href="/facts/Primordial_isotope/lFAUqHDv">primordial isotope</a>, <a href="/facts/Bismuth-209/Bxu7JrUs">bismuth-209</a>, was found in 2003 to be slightly <a href="/facts/Radioactive/Ya6FVjt4">radioactive</a>, decaying via <a href="/facts/Alpha_decay/rCsHNIUE">alpha decay</a> with a half-life more than a billion times the estimated <a href="/facts/Age_of_the_universe/BaByputq">age of the universe</a>. Prior to this discovery, bismuth-209 was thought to be the heaviest naturally occurring stable isotope;<a class="footnote-ref" id="fnref:118" href="#fn:118"><sup>118</sup></a> this distinction now belongs to lead-208.</li></ul> <p><a href="/facts/Uranium/n2sGWBzU">Uranium</a> </p> <ul><li>The only element with a naturally occurring isotope capable of undergoing nuclear fission is uranium.<a class="footnote-ref" id="fnref:119" href="#fn:119"><sup>119</sup></a> The capacity of <a href="/facts/Uranium-235/pe0RznDM">uranium-235</a> to undergo fission was first suggested (and ignored) in 1934, and subsequently discovered in 1938.<a class="footnote-ref" id="fnref:120" href="#fn:120"><sup>120</sup></a></li></ul> <p><a href="/facts/Plutonium/4bUw9zH3">Plutonium</a> </p> <ul><li>It is normally true that metals reduce their electrical conductivity when heated. Plutonium increases its electrical conductivity when heated in the temperature range of around –175 to +125 °C.<a class="footnote-ref" id="fnref:121" href="#fn:121"><sup>121</sup></a> There is evidence that this behavior, and similar with some of the other transuranic elements is due to more complex relativistic and spin interactions that are not captured by simple model of electrical conductivity.<a class="footnote-ref" id="fnref:122" href="#fn:122"><sup>122</sup></a></li></ul> <h3>Metalloids</h3> <p><a href="/facts/Boron/Pmwgd7Mf">Boron</a> </p> <ul><li>Boron is the only element with a partially disordered structure in its most thermodynamically stable crystalline form.<a class="footnote-ref" id="fnref:123" href="#fn:123"><sup>123</sup></a></li></ul> <p><a href="/facts/Boron/Pmwgd7Mf">Boron</a>, <a href="/facts/Antimony/YsA7lVgT">antimony</a> </p> <ul><li>These elements are record holders within the field of <a href="/facts/Superacid/dg82EcNa">superacid</a> chemistry. For seven decades, <a href="/facts/Fluorosulfonic_acid/HJng4DqN">fluorosulfonic acid</a> HSO3F and <a href="/facts/Trifluoromethanesulfonic_acid/NmKSuzxV">trifluoromethanesulfonic acid</a> CF3SO3H were the strongest known acids that could be isolated as single compounds. Both are about a thousand times more acidic than pure <a href="/facts/Sulfuric_acid/Wom6fymJ">sulfuric acid</a>. In 2004, a boron compound broke this record by a thousand fold with the synthesis of <a href="/facts/Carborane_acid/H02L5vw9">carborane acid</a> H(CHB11Cl11). Another metalloid, antimony, features in the strongest known acid, a mixture 10 billion times stronger than carborane acid. This is <a href="/facts/Fluoroantimonic_acid/HfSxCACr">fluoroantimonic acid</a> H2F[SbF6], a mixture of <a href="/facts/Antimony_pentafluoride/nTqasUkK">antimony pentafluoride</a> SbF5 and <a href="/facts/Hydrofluoric_acid/wdXqu4bE">hydrofluoric acid</a> HF.</li></ul> <p><a href="/facts/Silicon/cgWx0hdr">Silicon</a> </p> <ol><li>The thermal conductivity of silicon is better than that of most metals.</li> <li>A sponge-like <a href="/facts/Porous_silicon/lNxL71v2">porous form of silicon</a> (p-Si) is typically prepared by the electrochemical etching of silicon wafers in a <a href="/facts/Hydrofluoric_acid/wdXqu4bE">hydrofluoric acid</a> solution.<a class="footnote-ref" id="fnref:124" href="#fn:124"><sup>124</sup></a> Flakes of p-Si sometimes appear red;<a class="footnote-ref" id="fnref:125" href="#fn:125"><sup>125</sup></a> it has a band gap of 1.97–2.1 eV.<a class="footnote-ref" id="fnref:126" href="#fn:126"><sup>126</sup></a> The many tiny pores in porous silicon give it an enormous internal surface area, up to 1,000 m2/cm3.<a class="footnote-ref" id="fnref:127" href="#fn:127"><sup>127</sup></a> When exposed to an <a href="/facts/Oxidant/1FQzB8pQ">oxidant</a>,<a class="footnote-ref" id="fnref:128" href="#fn:128"><sup>128</sup></a> especially a liquid oxidant,<a class="footnote-ref" id="fnref:129" href="#fn:129"><sup>129</sup></a> the high surface-area to volume ratio of p-Si creates a very efficient burn, accompanied by nano-explosions,<a class="footnote-ref" id="fnref:130" href="#fn:130"><sup>130</sup></a> and sometimes by <a href="/facts/Ball_lightning/bmB4BpMB">ball-lightning</a>-like plasmoids with, for example, a diameter of 0.1–0.8 m, a velocity of up to 0.5 m/s and a lifetime of up to 1s.<a class="footnote-ref" id="fnref:131" href="#fn:131"><sup>131</sup></a> The first ever spectrographic analysis of a ball lightning event (in 2012) revealed the presence of silicon, iron and calcium, these elements also being present in the soil.<a class="footnote-ref" id="fnref:132" href="#fn:132"><sup>132</sup></a></li></ol> <p><a href="/facts/Arsenic/k1c4f44D">Arsenic</a> </p> <ul><li>Metals are said to be <a href="/facts/Melting/zhhDBo5V">fusible</a>, resulting in some confusion in old chemistry as to whether arsenic was a true metal, or a nonmetal, or something in-between. It <a href="/facts/Sublimation_(phase_transition)/KDoKokMn">sublimes</a> rather than melts at standard <a href="/facts/Atmospheric_pressure/wJLMSaVG">atmospheric pressure</a>, like the nonmetals <a href="/facts/Carbon/ukrgQexo">carbon</a> and <a href="/facts/Red_phosphorus/GarX3byj">red phosphorus</a>.</li></ul> <p><a href="/facts/Antimony/YsA7lVgT">Antimony</a> </p> <ul><li>A high-energy <a href="/facts/Explosive_antimony/eLcaSRq7">explosive form of antimony</a> was first produced in 1858. It is prepared by the electrolysis of any of the heavier antimony trihalides (SbCl3, SbBr3, SbI3) in a hydrochloric acid solution at low temperature. It comprises amorphous antimony with some occluded antimony trihalide (7–20% in the case of the <a href="/facts/Antimony_trichloride/8SCfjxeL">trichloride</a>). When scratched, struck, powdered or heated quickly to 200 °C, it "flares up, emits sparks and is converted explosively into the lower-energy, crystalline grey antimony".<a class="footnote-ref" id="fnref:133" href="#fn:133"><sup>133</sup></a></li></ul> <h3>Nonmetals</h3> <p><a href="/facts/Hydrogen/BoYHjl0J">Hydrogen</a> </p> <ol><li><a href="/facts/Water/0lkXnJPK">Water</a> (H2O), a well-known <a href="/facts/Oxide/DXtoVe1C">oxide</a> of hydrogen, is a spectacular anomaly.<a class="footnote-ref" id="fnref:134" href="#fn:134"><sup>134</sup></a> Extrapolating from the heavier <a href="/facts/Hydrogen_chalcogenide/pNCrhmwX">hydrogen chalcogenides</a>, namely <a href="/facts/Hydrogen_sulfide/UbCqjMMk">hydrogen sulfide</a> H2S, <a href="/facts/Hydrogen_selenide/l2Pn2wJo">hydrogen selenide</a> H2Se, and <a href="/facts/Hydrogen_telluride/o2AH0udB">hydrogen telluride</a> H2Te, water should be "a foul-smelling, poisonous, inflammable gas... condensing to a nasty liquid [at] around –100 °C". Instead, due to <a href="/facts/Hydrogen_bonding/85V86IIg">hydrogen bonding</a>, water is "stable, potable, odorless, benign, and... indispensable to life".<a class="footnote-ref" id="fnref:135" href="#fn:135"><sup>135</sup></a></li> <li>Less well-known of the oxides of hydrogen is the <a href="/facts/Hydrogen_trioxide/9S3ARK9m">trioxide</a>, H2O3. <a href="/facts/Marcellin_Berthelot/TaeR6uXD">Berthelot</a> proposed the existence of this oxide in 1880 but his suggestion was soon forgotten as there was no way of testing it using the technology of the time.<a class="footnote-ref" id="fnref:136" href="#fn:136"><sup>136</sup></a> Hydrogen trioxide was prepared in 1994 by replacing the oxygen used in the industrial process for making hydrogen peroxide, with <a href="/facts/Ozone/o0E5gn2p">ozone</a>. The yield is about 40 per cent, at –78 °C; above around –40 °C it decomposes into water and oxygen.<a class="footnote-ref" id="fnref:137" href="#fn:137"><sup>137</sup></a> Derivatives of hydrogen trioxide, such as F3C–O–O–O–CF3 ("bis(trifluoromethyl) trioxide") are known; these are <a href="/facts/Metastable/H72SMWof">metastable</a> at room temperature.<a class="footnote-ref" id="fnref:138" href="#fn:138"><sup>138</sup></a> <a href="/facts/Mendeleev/xdouRrx8">Mendeleev</a> went a step further, in 1895, and proposed the existence of <a href="/facts/Hydrogen_tetroxide/7KpxP483">hydrogen tetroxide</a> HO–O–O–OH as a transient intermediate in the decomposition of hydrogen peroxide;<a class="footnote-ref" id="fnref:139" href="#fn:139"><sup>139</sup></a> this was prepared and characterised in 1974, using a matrix isolation technique. <a href="/facts/Alkali_metal/IkWbCLk2">Alkali metal</a> <a href="/facts/Ozonide/o5dokpaf">ozonide</a> salts of the unknown <a href="/facts/Hydrogen_ozonide/W6AM475G">hydrogen ozonide</a> (HO3) are also known; these have the formula MO3.<a class="footnote-ref" id="fnref:140" href="#fn:140"><sup>140</sup></a></li></ol> <p><a href="/facts/Helium/yRul93TG">Helium</a> </p> <ol><li>At temperatures below 0.3 and 0.8 K respectively, <a href="/facts/Helium-3/SmPC5oT3">helium-3</a> and <a href="/facts/Helium-4/vNsL5qhC">helium-4</a> each have a negative <a href="/facts/Enthalpy_of_fusion/eLJIURcp">enthalpy of fusion</a>. This means that, at the appropriate constant pressures, these substances freeze with the <i>addition</i> of heat.</li> <li>Until 1999 helium was thought to be too small to form a cage <a href="/facts/Clathrate/QYoBcBg1">clathrate</a>—a compound in which a guest atom or molecule is encapsulated in a cage formed by a host molecule—at atmospheric pressure. In that year the synthesis of microgram quantities of <a href="/facts/Dodecahedrane/h4ySsxVh">He@C20H20</a> represented the first such helium clathrate and (what was described as) the world's smallest helium balloon.<a class="footnote-ref" id="fnref:141" href="#fn:141"><sup>141</sup></a></li></ol> <p><a href="/facts/Carbon/ukrgQexo">Carbon</a> </p> <ol><li>Graphite is the most electrically conductive nonmetal, better than some metals.</li> <li><a href="/facts/Diamond/IBUdnd1y">Diamond</a> is the best natural conductor of heat; it even feels cold to the touch. Its thermal conductivity (2,200 W/m•K) is five times greater than the most conductive metal (<a href="/facts/Silver/xXe41BGg">Ag</a> at 429); 300 times higher than the least conductive metal (<a href="/facts/Plutonium/4bUw9zH3">Pu</a> at 6.74); and nearly 4,000 times that of water (0.58) and 100,000 times that of air (0.0224). This high thermal conductivity is used by jewelers and gemologists to separate diamonds from imitations.</li> <li>Graphene <a href="/facts/Aerogel/cjhmCvSa">aerogel</a>, produced in 2012 by freeze-drying a solution of <a href="/facts/Carbon_nanotube/atuDPPaG">carbon nanotubes</a> and <a href="/facts/Graphite_oxide/mxo0EJJl">graphite oxide</a> sheets and chemically removing oxygen, is seven times lighter than air, and ten per cent lighter than helium. It is the lightest solid known (0.16 mg/cm3), conductive and elastic.<a class="footnote-ref" id="fnref:142" href="#fn:142"><sup>142</sup></a></li></ol> <p><a href="/facts/Phosphorus/27xCeIqs">Phosphorus</a> </p> <ul><li>The least stable and most reactive form of phosphorus is the <a href="/facts/Allotropes_of_phosphorus/GarX3byj">white</a> <a href="/facts/Allotrope/2WUdHWxg">allotrope</a>. It is a hazardous, highly flammable and toxic substance, spontaneously igniting in air and producing <a href="/facts/Phosphoric_acid/l6NbwyCv">phosphoric acid</a> residue. It is therefore normally stored under water. White phosphorus is also the most common, industrially important, and easily reproducible allotrope, and for these reasons is regarded as the <a href="/facts/Standard_state/adrN3C0a">standard state</a> of phosphorus. The most stable form is the <a href="/facts/Allotropes_of_phosphorus/GarX3byj">black allotrope</a>, which is a metallic looking, brittle and relatively non-reactive semiconductor (unlike the white allotrope, which has a white or yellowish appearance, is pliable, highly reactive and a semiconductor). When assessing periodicity in the physical properties of the elements it needs to be borne in mind that the quoted properties of phosphorus tend to be those of its least stable form rather than, as is the case with all other elements, the most stable form.</li></ul> <p><a href="/facts/Iodine/JlfMecMf">Iodine</a> </p> <ul><li>The mildest of the <a href="/facts/Halogen/YeFgWHeA">halogens</a>, iodine is the active ingredient in <a href="/facts/Tincture_of_iodine/BtmHsmpD">tincture of iodine</a>, a disinfectant. This can be found in household medicine cabinets or emergency survival kits. Tincture of iodine will rapidly dissolve gold,<a class="footnote-ref" id="fnref:143" href="#fn:143"><sup>143</sup></a> a task ordinarily requiring the use of <a href="/facts/Aqua_regia/AHr1mobH">aqua regia</a> (a highly corrosive mixture of <a href="/facts/Nitric_acid/UDbwGp6s">nitric</a> and <a href="/facts/Hydrochloric_acid/HqItJlUT">hydrochloric acids</a>).</li></ul> <h2 id="notes">Notes</h2> <h2 id="citations">Citations</h2> <ul><li>Addison WE 1964, <i>The allotropy of the elements</i>, Oldbourne Press, London</li> <li>Adler D 1969, 'Half-way elements: The technology of metalloids', book review, <i>Technology Review</i>, vol. 72, no. 1, Oct/Nov, pp. 18–19</li> <li>Benedict M, Alvarez LW, Bliss LA, English SG, Kinzell AB, Morrison P, English FH, Starr C & Williams WJ 1946, 'Technological control of atomic energy activities', "Bulletin of the Atomic Scientists", vol. 2, no. 11, pp. 18–29</li> <li>Anthony S 2013, <a href="https://www.extremetech.com/extreme/153063-graphene-aerogel-is-seven-times-lighter-than-air-can-balance-on-a-blade-of-grass">'Graphene aerogel is seven times lighter than air, can balance on a blade of grass'</a>, <i>ExtremeTech</i>, April 10, accessed 8 February 2015</li> <li>Antia, Meher. 1998, <a href="https://physics.aps.org/story/v2/st4">'Focus: Levitating Liquid Boron'</a>, <i>American Physical Society</i>, viewed 14 December 2014</li> <li>Appalakondaiah, S.; Vaitheeswaran, G.; Lebègue, S.; Christensen, N. E.; Svane, A. (2012-07-05). "Effect of van der Waals interactions on the structural and elastic properties of black phosphorus". <i>Physical Review B</i>. 86 (3). American Physical Society (APS): 035105. <a href="/facts/ArXiv_(identifier)/H6EtgnBe">arXiv</a>:<a href="https://arxiv.org/abs/1211.3512">1211.3512</a>. <a href="/facts/Bibcode_(identifier)/9HtdQSGB">Bibcode</a>:<a href="https://ui.adsabs.harvard.edu/abs/2012PhRvB..86c5105A">2012PhRvB..86c5105A</a>. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1103%2Fphysrevb.86.035105">10.1103/physrevb.86.035105</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/1098-0121">1098-0121</a>. <a href="/facts/S2CID_(identifier)/ldJsHa2Y">S2CID</a> <a href="https://api.semanticscholar.org/CorpusID:118356764">118356764</a>.</li> <li>Askeland DR, Fulay PP & Wright JW 2011, <i>The science and engineering of materials</i>, 6th ed., Cengage Learning, Stamford, CT, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 0-495-66802-8</li> <li>Atkins P, Overton T, Rourke J, Weller M & Armstrong F 2006, <i>Shriver & Atkins' inorganic chemistry</i>, 4th ed., Oxford University Press, Oxford, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 0-7167-4878-9</li> <li>Austen K 2012, 'A factory for elements that barely exist', <i>NewScientist</i>, 21 Apr, p. 12, ISSN 1032-1233</li> <li>Bagnall KW 1966, <i>The chemistry of selenium, tellurium and polonium</i>, Elsevier, Amsterdam</li> <li>Bailar JC, Moeller T, Kleinberg J, Guss CO, Castellion ME & Metz C 1989, <i>Chemistry</i>, 3rd ed., Harcourt Brace Jovanovich, San Diego, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 0-15-506456-8</li> <li>Bassett LG, Bunce SC, Carter AE, Clark HM & Hollinger HB 1966, <i>Principles of chemistry</i>, Prentice-Hall, Englewood Cliffs, NJ</li> <li>Batsanov SS & Batsanov AS 2012, <i>Introduction to structural chemistry</i>, Springer Science+Business Media, Dordrecht, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 978-94-007-4770-8</li> <li>Berei K & Vasáros L 1985, 'Astatine compounds', in Kugler & Keller</li> <li>Betke, Ulf; Wickleder, Mathias S. (2011-01-05). "Sulfates of the Refractory Metals: Crystal Structure and Thermal Behavior of Nb2O2(SO4)3, MoO2(SO4), WO(SO4)2, and Two Modifications of Re2O5(SO4)2". <i>Inorganic Chemistry</i>. 50 (3). American Chemical Society (ACS): 858–872. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1021%2Fic101455z">10.1021/ic101455z</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/0020-1669">0020-1669</a>. <a href="/facts/PMID_(identifier)/JlHAvMHt">PMID</a> <a href="https://pubmed.ncbi.nlm.nih.gov/21207946">21207946</a>.</li> <li>Beveridge TJ, Hughes MN, Lee H, Leung KT, Poole RK, Savvaidis I, Silver S & Trevors JT 1997, 'Metal–microbe interactions: Contemporary approaches', in RK Poole (ed.), <i>Advances in microbial physiology</i>, vol. 38, Academic Press, San Diego, pp. 177–243, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 0-12-027738-7</li> <li>Bogoroditskii NP & Pasynkov VV 1967, <i>Radio and electronic materials</i>, Iliffe Books, London</li> <li>Booth VH & Bloom ML 1972, <i>Physical science: a study of matter and energy</i>, Macmillan, New York</li> <li>Born M & Wolf E 1999, <i><a href="/facts/Principles_of_Optics/n8GWeqIs">Principles of optics: Electromagnetic theory of propagation, interference and diffraction of light</a></i>, 7th ed., Cambridge University Press, Cambridge, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 0-521-64222-1</li> <li>Brassington, M. P.; Lambson, W. A.; Miller, A. J.; Saunders, G. A.; Yogurtçu, Y. K. (1980). "The second- and third-order elastic constants of amorphous arsenic". <i>Philosophical Magazine B</i>. 42 (1). Informa UK Limited: 127–148. <a href="/facts/Bibcode_(identifier)/9HtdQSGB">Bibcode</a>:<a href="https://ui.adsabs.harvard.edu/abs/1980PMagB..42..127B">1980PMagB..42..127B</a>. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1080%2F01418638008225644">10.1080/01418638008225644</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/1364-2812">1364-2812</a>.</li> <li>Brasted RC 1974, 'Oxygen group elements and their compounds', in <i>The new Encyclopædia Britannica</i>, vol. 13, Encyclopædia Britannica, Chicago, pp. 809–824</li> <li>Brescia F, Arents J, Meislich H & Turk A 1975, <i>Fundamentals of chemistry</i>, 3rd ed., Academic Press, New York, p. 453, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 978-0-12-132372-1</li> <li>Brinkley SR 1945, <i>Introductory general chemistry</i>, 3rd ed., Macmillan, New York</li> <li>Brown TL, LeMay HE, Bursten BE, Murphy CJ & Woodward P 2009, <i>Chemistry: The Central Science</i>, 11th ed., Pearson Education, New Jersey, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 978-0-13-235-848-4</li> <li>Burakowski T & Wierzchoń T 1999, <i>Surface engineering of metals: Principles, equipment, technologies</i>, CRC Press, Boca Raton, Fla, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 0-8493-8225-4</li> <li>Bychkov VL 2012, 'Unsolved Mystery of Ball Lightning', in <i>Atomic Processes in Basic and Applied Physics</i>, V Shevelko & H Tawara (eds), Springer Science & Business Media, Heidelberg, pp. 3–24, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 978-3-642-25568-7</li> <li>Carapella SC 1968a, 'Arsenic' in CA Hampel (ed.), <i>The encyclopedia of the chemical elements</i>, Reinhold, New York, pp. 29–32</li> <li>Cerkovnik, Janez; Plesničar, Božo (2013-06-28). "Recent Advances in the Chemistry of Hydrogen Trioxide (HOOOH)". <i>Chemical Reviews</i>. 113 (10). American Chemical Society (ACS): 7930–7951. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1021%2Fcr300512s">10.1021/cr300512s</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/0009-2665">0009-2665</a>. <a href="/facts/PMID_(identifier)/JlHAvMHt">PMID</a> <a href="https://pubmed.ncbi.nlm.nih.gov/23808683">23808683</a>.</li> <li>Chang R 1994, <i>Chemistry</i>, 5th (international) ed., McGraw-Hill, New York</li> <li>Chang R 2002, <i>Chemistry</i>, 7th ed., McGraw Hill, Boston</li> <li>Chedd G 1969, <i>Half-way elements: The technology of metalloids</i>, Doubleday, New York</li> <li>Chen, Zhiliang; Lee, Tzung-Yin; Bosman, Gijs (1994-06-20). "Electrical band gap of porous silicon". <i>Applied Physics Letters</i>. 64 (25). AIP Publishing: 3446–3448. <a href="/facts/Bibcode_(identifier)/9HtdQSGB">Bibcode</a>:<a href="https://ui.adsabs.harvard.edu/abs/1994ApPhL..64.3446C">1994ApPhL..64.3446C</a>. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1063%2F1.111237">10.1063/1.111237</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/0003-6951">0003-6951</a>.</li> <li>Chizhikov DM & Shchastlivyi VP 1968, <i>Selenium and selenides</i>, translated from the Russian by EM Elkin, Collet's, London</li> <li>Choppin GR & Johnsen RH 1972, <i>Introductory chemistry</i>, Addison-Wesley, Reading, Massachusetts</li> <li>Christensen RM 2012, 'Are the elements ductile or brittle: A nanoscale evaluation', in <i><a href="https://www.failurecriteria.com/">Failure theory for materials science and engineering</a></i>, chapter 12, p. 14</li> <li>Clementi, E.; Raimondi, D. L. (1963). "Atomic Screening Constants from SCF Functions". <i>The Journal of Chemical Physics</i>. 38 (11). AIP Publishing: 2686–2689. <a href="/facts/Bibcode_(identifier)/9HtdQSGB">Bibcode</a>:<a href="https://ui.adsabs.harvard.edu/abs/1963JChPh..38.2686C">1963JChPh..38.2686C</a>. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1063%2F1.1733573">10.1063/1.1733573</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/0021-9606">0021-9606</a>.</li> <li>Clementi, E.; Raimondi, D. L.; Reinhardt, W. P. (1967-08-15). "Atomic Screening Constants from SCF Functions. II. Atoms with 37 to 86 Electrons". <i>The Journal of Chemical Physics</i>. 47 (4). AIP Publishing: 1300–1307. <a href="/facts/Bibcode_(identifier)/9HtdQSGB">Bibcode</a>:<a href="https://ui.adsabs.harvard.edu/abs/1967JChPh..47.1300C">1967JChPh..47.1300C</a>. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1063%2F1.1712084">10.1063/1.1712084</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/0021-9606">0021-9606</a>.</li> <li>Cordes EH & Scaheffer R 1973, <i>Chemistry</i>, Harper & Row, New York</li> <li>Cotton SA 1994, 'Scandium, yttrium & the lanthanides: Inorganic & coordination chemistry', in RB King (ed.), <i>Encyclopedia of inorganic chemistry</i>, 2nd ed., vol. 7, John Wiley & Sons, New York, pp. 3595–3616, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 978-0-470-86078-6</li> <li>Cox PA 2004, <i>Inorganic chemistry</i>, 2nd ed., Instant notes series, Bios Scientific, London, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 1-85996-289-0</li> <li>Cross, R. James; Saunders, Martin; Prinzbach, Horst (1999-09-29). "Putting Helium Inside Dodecahedrane". <i>Organic Letters</i>. 1 (9). American Chemical Society (ACS): 1479–1481. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1021%2Fol991037v">10.1021/ol991037v</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/1523-7060">1523-7060</a>.</li> <li>Cverna F 2002, <i>ASM ready reference: Thermal properties of metals</i>, ASM International, Materials Park, Ohio, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 0-87170-768-3</li> <li>Dalhouse University 2015, <a href="https://www.dal.ca/news/media/media-releases/2015/01/28/dal_chemist_discovers_new_information_about_elemental_boron.html">'Dal chemist discovers new information about elemental boron'</a>, media release, 28 January, accessed 9 May 2015</li> <li>Deming HG 1952, <i>General chemistry: An elementary survey</i>, 6th ed., John Wiley & Sons, New York</li> <li>Desai, P. D.; James, H. M.; Ho, C. Y. (1984). <a href="https://srd.nist.gov/JPCRD/jpcrd260.pdf">"Electrical Resistivity of Aluminum and Manganese"</a> (PDF). <i>Journal of Physical and Chemical Reference Data</i>. 13 (4). AIP Publishing: 1131–1172. <a href="/facts/Bibcode_(identifier)/9HtdQSGB">Bibcode</a>:<a href="https://ui.adsabs.harvard.edu/abs/1984JPCRD..13.1131D">1984JPCRD..13.1131D</a>. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1063%2F1.555725">10.1063/1.555725</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/0047-2689">0047-2689</a>.</li> <li>Donohoe J 1982, <i>The Structures of the Elements</i>, Robert E. Krieger, Malabar, Florida, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 0-89874-230-7</li> <li>Douglade, J.; Mercier, R. (1982-03-15). "Structure cristalline et covalence des liaisons dans le sulfate d'arsenic(III), As2(SO4)3". <i>Acta Crystallographica Section B: Structural Crystallography and Crystal Chemistry</i>. 38 (3). International Union of Crystallography (IUCr): 720–723. <a href="/facts/Bibcode_(identifier)/9HtdQSGB">Bibcode</a>:<a href="https://ui.adsabs.harvard.edu/abs/1982AcCrB..38..720D">1982AcCrB..38..720D</a>. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1107%2Fs056774088200394x">10.1107/s056774088200394x</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/0567-7408">0567-7408</a>.</li> <li>Dumé, Belle (23 April 2003). <a href="https://physicsworld.com/a/bismuth-breaks-half-life-record-for-alpha-decay/">"Bismuth breaks half-life record for alpha decay"</a>. Physicsworld.</li> <li>Dunstan S 1968, <i>Principles of chemistry</i>, D. Van Nostrand Company, London</li> <li>Du Plessis M 2007, 'A Gravimetric Technique to Determine the Crystallite Size Distribution in High Porosity Nanoporous Silicon, in JA Martino, MA Pavanello & C Claeys (eds), <i>Microelectronics Technology and Devices–SBMICRO 2007</i>, vol. 9, no. 1, The Electrochemical Society, New Jersey, pp. 133–142, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 978-1-56677-565-6</li> <li>Eby GS, Waugh CL, Welch HE & Buckingham BH 1943, <i>The physical sciences</i>, Ginn and Company, Boston</li> <li>Edwards, Peter P.; Sienko, M. J. (1983). "On the occurrence of metallic character in the periodic table of the elements". <i>Journal of Chemical Education</i>. 60 (9). American Chemical Society (ACS): 691–696. <a href="/facts/Bibcode_(identifier)/9HtdQSGB">Bibcode</a>:<a href="https://ui.adsabs.harvard.edu/abs/1983JChEd..60..691E">1983JChEd..60..691E</a>. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1021%2Fed060p691">10.1021/ed060p691</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/0021-9584">0021-9584</a>.</li> <li>Edwards PP 1999, 'Chemically engineering the metallic, insulating and superconducting state of matter' in KR Seddon & M Zaworotko (eds), <i>Crystal engineering: The design and application of functional solids</i>, Kluwer Academic, Dordrecht, pp. 409–431</li> <li>Edwards PP 2000, 'What, why and when is a metal?', in N Hall (ed.), <i>The new chemistry</i>, Cambridge University, Cambridge, pp. 85–114</li> <li>Edwards, P. P.; Lodge, M. T. J.; Hensel, F.; Redmer, R. (2010-03-13). <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3263814">"'… a metal conducts and a non-metal doesn't'"</a>. <i>Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences</i>. 368 (1914): 941–965. <a href="/facts/Bibcode_(identifier)/9HtdQSGB">Bibcode</a>:<a href="https://ui.adsabs.harvard.edu/abs/2010RSPTA.368..941E">2010RSPTA.368..941E</a>. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1098%2Frsta.2009.0282">10.1098/rsta.2009.0282</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/1364-503X">1364-503X</a>. <a href="/facts/PMC_(identifier)/dX1zMt71">PMC</a> <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3263814">3263814</a>. <a href="/facts/PMID_(identifier)/JlHAvMHt">PMID</a> <a href="https://pubmed.ncbi.nlm.nih.gov/20123742">20123742</a>.</li> <li>Eichler, R.; et al. (2007). "Chemical characterization of element 112". <i>Nature</i>. 447 (7140): 72–75. <a href="/facts/Bibcode_(identifier)/9HtdQSGB">Bibcode</a>:<a href="https://ui.adsabs.harvard.edu/abs/2007Natur.447...72E">2007Natur.447...72E</a>. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1038%2Fnature05761">10.1038/nature05761</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/0028-0836">0028-0836</a>. <a href="/facts/PMID_(identifier)/JlHAvMHt">PMID</a> <a href="https://pubmed.ncbi.nlm.nih.gov/17476264">17476264</a>.</li> <li>Emsley 1994, 'Science: Surprise legacy of Germany's Flying Bombs', <i>New Scientist</i>, no. 1910, January 29</li> <li>Emsley J 2001, <i><a href="https://books.google.com/books?id=Yhi5X7OwuGkC">Nature's building blocks: An A–Z guide to the elements</a></i>, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 0-19-850341-5</li> <li>Endicott K 1998, <a href="https://web.archive.org/web/20140715003519/http://stemed.unm.edu/PDFs/cd/CLASSROOM_LAB_SAFETY/Trembling_Edge_Science.pdf">'The Trembling Edge of Science'</a>, <i>Dartmouth Alumini Magazine</i>, April, accessed 8 May 2015</li> <li>Fraden, J. H. (1951). "Amorphous antimony. A lecture demonstration in allotropy". <i>Journal of Chemical Education</i>. 28 (1): 34-35. <a href="/facts/Bibcode_(identifier)/9HtdQSGB">Bibcode</a>:<a href="https://ui.adsabs.harvard.edu/abs/1951JChEd..28...34F">1951JChEd..28...34F</a>. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1021%2Fed028p34">10.1021/ed028p34</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/0021-9584">0021-9584</a>.</li> <li>Furuseth, Sigrid; Selte, Kari; Hope, Håkon; Kjekshus, Arne; Klewe, Bernt; Powell, D. L. (1974). "Iodine Oxides. Part V. The Crystal Structure of (IO)2SO4". <i>Acta Chemica Scandinavica</i>. 28a: 71–76. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.3891%2Facta.chem.scand.28a-0071">10.3891/acta.chem.scand.28a-0071</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/0904-213X">0904-213X</a>.</li> <li>Georgievskii VI 1982, 'Biochemical regions. Mineral composition of feeds', in VI Georgievskii, BN Annenkov & VT Samokhin (eds), <i>Mineral nutrition of animals: Studies in the agricultural and food sciences</i>, Butterworths, London, pp. 57–68, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 0-408-10770-7</li> <li>Gillespie RJ & Robinson EA 1959, 'The sulphuric acid solvent system', in HJ Emeléus & AG Sharpe (eds), <i>Advances in inorganic chemistry and radiochemistry</i>, vol. 1, Academic Press, New York, pp. 386–424</li> <li>Glazov VM, Chizhevskaya SN & Glagoleva NN 1969, <i>Liquid semiconductors</i>, Plenum, New York</li> <li>Glinka N 1965, <i>General chemistry</i>, trans. D Sobolev, Gordon & Breach, New York</li> <li>Gösele U & Lehmann V 1994, 'Porous Silicon Quantum Sponge Structures: Formation Mechanism, Preparation Methods and Some Properties', in Feng ZC & Tsu R (eds), <i>Porous Silicon</i>, World Scientific, Singapore, pp. 17–40, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 981-02-1634-3</li> <li>Greaves, G. N.; Greer, A. L.; Lakes, R. S.; Rouxel, T. (2011). "Poisson's ratio and modern materials". <i>Nature Materials</i>. 10 (11): 823–837. <a href="/facts/Bibcode_(identifier)/9HtdQSGB">Bibcode</a>:<a href="https://ui.adsabs.harvard.edu/abs/2011NatMa..10..823G">2011NatMa..10..823G</a>. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1038%2Fnmat3134">10.1038/nmat3134</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/1476-1122">1476-1122</a>. <a href="/facts/PMID_(identifier)/JlHAvMHt">PMID</a> <a href="https://pubmed.ncbi.nlm.nih.gov/22020006">22020006</a>.</li> <li>Greenwood NN & Earnshaw A 2002, <i>Chemistry of the elements</i>, 2nd ed., Butterworth-Heinemann, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 0-7506-3365-4</li> <li>Gschneidner, Karl A. (1964). "Physical Properties and Interrelationships of Metallic and Semimetallic Elements". <i>Solid State Physics</i>. Vol. 16. Elsevier. p. 275-426. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1016%2Fs0081-1947%2808%2960518-4">10.1016/s0081-1947(08)60518-4</a>. <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 978-0-12-607716-2. {{cite book}}: ISBN / Date incompatibility (help)</li> <li>Gupta A, Awana VPS, Samanta SB, Kishan H & Narlikar AV 2005, 'Disordered superconductors' in AV Narlikar (ed.), <a href="https://books.google.com/books?id=F_-CN0tVqjAC&pg=PA502"><i>Frontiers in superconducting materials</i></a>, Springer-Verlag, Berlin, p. 502, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 3-540-24513-8</li> <li>Habashi F 2003, <i>Metals from ores: an introduction to extractive metallurgy</i>, Métallurgie Extractive Québec, Sainte Foy, Québec, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 2-922686-04-3</li> <li>Manson SS & Halford GR 2006, <i>Fatigue and Durability of Structural Materials</i>, ASM International, Materials Park, OH, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 0-87170-825-6</li> <li>Hampel CA & Hawley GG 1976, <i>Glossary of chemical terms</i>, Van Nostrand Reinhold, New York</li> <li>Hem JD 1985, <i>Study and interpretation of the chemical characteristics of natural water</i>, paper 2254, 3rd ed., US Geological Society, Alexandria, Virginia</li> <li>Hérold, Albert (2005-12-28). <a href="https://doi.org/10.1016%2Fj.crci.2005.10.002">"An arrangement of the chemical elements in several classes inside the periodic table according to their common properties"</a>. <i>Comptes Rendus. Chimie</i>. 9 (1): 148–153. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1016%2Fj.crci.2005.10.002">10.1016/j.crci.2005.10.002</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/1878-1543">1878-1543</a>.</li> <li>Herzfeld, K. F. (1927-05-01). "On Atomic Properties which make an Element a Metal". <i>Physical Review</i>. 29 (5): 701–705. <a href="/facts/Bibcode_(identifier)/9HtdQSGB">Bibcode</a>:<a href="https://ui.adsabs.harvard.edu/abs/1927PhRv...29..701H">1927PhRv...29..701H</a>. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1103%2FPhysRev.29.701">10.1103/PhysRev.29.701</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/0031-899X">0031-899X</a>.</li> <li>Heslop RB & Robinson PL 1963, <i>Inorganic chemistry: A guide to advanced study</i>, Elsevier, Amsterdam</li> <li>Hill G & Holman J 2000, <a href="https://books.google.com/books?id=90IqK540a9AC"><i>Chemistry in context</i></a>, 5th ed., Nelson Thornes, Cheltenham, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 0-17-448307-4</li> <li>Hiller LA & Herber RH 1960, <i>Principles of chemistry</i>, McGraw-Hill, New York</li> <li>Holtzclaw HF, Robinson WR & Odom JD 1991, <i>General chemistry</i>, 9th ed., DC Heath, Lexington, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 0-669-24429-5</li> <li>Hopcroft, Matthew A.; Nix, William D.; Kenny, Thomas W. (2010). "What is the Young's Modulus of Silicon?". <i>Journal of Microelectromechanical Systems</i>. 19 (2): 229–238. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1109%2FJMEMS.2009.2039697">10.1109/JMEMS.2009.2039697</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/1057-7157">1057-7157</a>.</li> <li><i>Chemistry Views</i> 2012, 'Horst Prinzbach (1931 – 2012)', Wiley-VCH, accessed 28 February 2015</li> <li>Huheey JE, Keiter EA & Keiter RL 1993, <i>Principles of Structure & Reactivity</i>, 4th ed., HarperCollins College Publishers, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 0-06-042995-X</li> <li>Hultgren HH 1966, 'Metalloids', in GL Clark & GG Hawley (eds), <i>The encyclopedia of inorganic chemistry</i>, 2nd ed., Reinhold Publishing, New York</li> <li>Hunt A 2000, <i>The complete A-Z chemistry handbook</i>, 2nd ed., Hodder & Stoughton, London</li> <li>Iler RK 1979, <i>The chemistry of silica: solubility, polymerization, colloid and surface properties, and biochemistry</i>, John Wiley, New York, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 978-0-471-02404-0</li> <li>Jackson, Mike (2000). <a href="https://drive.google.com/file/d/1URM-lnZjqDVTsMmUCuwXCrmWTiYmTVD_/view">"Wherefore Gadolinium? Magnetism of the Rare Earths"</a>. <i>IRM Quarterly</i>. 10 (3). Institute for Rock Magnetism: 6. <a href="https://web.archive.org/web/20170712151422/http://www.irm.umn.edu/quarterly/irmq10-3.pdf">Archived</a> (PDF) from the original on 2017-07-12. Retrieved 2016-08-08.</li> <li>Jansen, Martin (2005-11-30). <a href="https://doi.org/10.1016%2Fj.solidstatesciences.2005.06.015">"Effects of relativistic motion of electrons on the chemistry of gold and platinum"</a>. <i>Solid State Sciences</i>. 7 (12): 1464–1474. <a href="/facts/Bibcode_(identifier)/9HtdQSGB">Bibcode</a>:<a href="https://ui.adsabs.harvard.edu/abs/2005SSSci...7.1464J">2005SSSci...7.1464J</a>. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1016%2Fj.solidstatesciences.2005.06.015">10.1016/j.solidstatesciences.2005.06.015</a>.</li> <li>Jauncey GEM 1948, <i>Modern physics: A second course in college physics</i>, D. Von Nostrand, New York</li> <li>Jenkins GM & Kawamura K 1976, <i>Polymeric carbons—carbon fibre, glass and char</i>, Cambridge University Press, Cambridge</li> <li>Keenan CW, Kleinfelter DC & Wood JH 1980, <i>General college chemistry</i>, 6th ed., Harper & Row, San Francisco, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 0-06-043615-8</li> <li>Keogh DW 2005, 'Actinides: Inorganic & coordination chemistry', in RB King (ed.), <i>Encyclopedia of inorganic chemistry</i>, 2nd ed., vol. 1, John Wiley & Sons, New York, pp. 2–32, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 978-0-470-86078-6</li> <li>Klein CA & Cardinale GF 1992, 'Young's modulus and Poisson's ratio of CVD diamond', in A Feldman & S Holly, <i>SPIE Proceedings</i>, vol. 1759, Diamond Optics V, pp. 178‒192, <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1117%2F12.130771">10.1117/12.130771</a></li> <li>Kneen WR, Rogers MJW & Simpson P 1972, <i>Chemistry: Facts, patterns, and principles</i>, Addison-Wesley, London</li> <li>Kovalev, D.; Timoshenko, V. Yu.; Künzner, N.; Gross, E.; Koch, F. (2001-07-19). "Strong Explosive Interaction of Hydrogenated Porous Silicon with Oxygen at Cryogenic Temperatures". <i>Physical Review Letters</i>. 87 (6): 068301. <a href="/facts/Bibcode_(identifier)/9HtdQSGB">Bibcode</a>:<a href="https://ui.adsabs.harvard.edu/abs/2001PhRvL..87f8301K">2001PhRvL..87f8301K</a>. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1103%2FPhysRevLett.87.068301">10.1103/PhysRevLett.87.068301</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/0031-9007">0031-9007</a>. <a href="/facts/PMID_(identifier)/JlHAvMHt">PMID</a> <a href="https://pubmed.ncbi.nlm.nih.gov/11497868">11497868</a>.</li> <li>Kozyrev PT 1959, 'Deoxidized selenium and the dependence of its electrical conductivity on pressure. II', <i>Physics of the solid state</i>, translation of the journal Solid State Physics (Fizika tverdogo tela) of the Academy of Sciences of the USSR, vol. 1, pp. 102–110</li> <li>Kugler HK & Keller C (eds) 1985, <i>Gmelin Handbook of Inorganic and Organometallic chemistry</i>, 8th ed., 'At, Astatine', system no. 8a, Springer-Verlag, Berlin, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 3-540-93516-9</li> <li>Lagrenaudie J 1953, 'Semiconductive properties of boron' (in French), <i>Journal de chimie physique</i>, vol. 50, nos. 11–12, Nov-Dec, pp. 629–633</li> <li>Lazaruk, S. K.; Dolbik, A. V.; Labunov, V. A.; Borisenko, V. E. (2007). "Combustion and explosion of nanostructured silicon in microsystem devices". <i>Semiconductors</i>. 41 (9): 1113–1116. <a href="/facts/Bibcode_(identifier)/9HtdQSGB">Bibcode</a>:<a href="https://ui.adsabs.harvard.edu/abs/2007Semic..41.1113L">2007Semic..41.1113L</a>. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1134%2FS1063782607090175">10.1134/S1063782607090175</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/1063-7826">1063-7826</a>.</li> <li>Legut, Dominik; Friák, Martin; Šob, Mojmír (2010-06-22). "Phase stability, elasticity, and theoretical strength of polonium from first principles". <i>Physical Review B</i>. 81 (21): 214118. <a href="/facts/Bibcode_(identifier)/9HtdQSGB">Bibcode</a>:<a href="https://ui.adsabs.harvard.edu/abs/2010PhRvB..81u4118L">2010PhRvB..81u4118L</a>. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1103%2FPhysRevB.81.214118">10.1103/PhysRevB.81.214118</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/1098-0121">1098-0121</a>.</li> <li>Leith MM 1966, Velocity of sound in solid iodine, MSc thesis, University of British Columbia. Leith comments that, '... as iodine is anisotropic in many of its physical properties most attention was paid to two amorphous samples which were thought to give representative average values of the properties of iodine' (p. iii).</li> <li>Lide DR & Frederikse HPR (eds) 1998, <i>CRC Handbook of chemistry and physics</i>, 79th ed., CRC Press, Boca Raton, Florida, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 0-849-30479-2</li> <li>Lidin RA 1996, <i>Inorganic substances handbook</i>, Begell House, New York, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 1-56700-065-7</li> <li>Andersen, A. Lindegaard; Dahle, Birgit (1966-01-01). "Fracture Phenomena in Amorphous Selenium". <i>Journal of Applied Physics</i>. 37 (1): 262–266. <a href="/facts/Bibcode_(identifier)/9HtdQSGB">Bibcode</a>:<a href="https://ui.adsabs.harvard.edu/abs/1966JAP....37..262A">1966JAP....37..262A</a>. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1063%2F1.1707823">10.1063/1.1707823</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/0021-8979">0021-8979</a>.</li> <li>Mann, Joseph B.; Meek, Terry L.; Allen, Leland C. (2000-03-01). "Configuration Energies of the Main Group Elements". <i>Journal of the American Chemical Society</i>. 122 (12): 2780–2783. <a href="/facts/Bibcode_(identifier)/9HtdQSGB">Bibcode</a>:<a href="https://ui.adsabs.harvard.edu/abs/2000JAChS.122.2780M">2000JAChS.122.2780M</a>. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1021%2Fja992866e">10.1021/ja992866e</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/0002-7863">0002-7863</a>.</li> <li>Marlowe MO 1970, <i>Elastic properties of three grades of fine grained graphite to 2000 °C</i>, NASA CR‒66933, National Aeronautics and Space Administration, Scientific and Technical Information Facility, College Park, Maryland</li> <li>Martienssen W & Warlimont H (eds) 2005, <i>Springer Handbook of Condensed Matter and Materials Data</i>, Springer, Heidelberg, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 3-540-30437-1</li> <li>Matula, R. A. (1979-10-01). "Electrical resistivity of copper, gold, palladium, and silver". <i>Journal of Physical and Chemical Reference Data</i>. 8 (4): 1147–1298. <a href="/facts/Bibcode_(identifier)/9HtdQSGB">Bibcode</a>:<a href="https://ui.adsabs.harvard.edu/abs/1979JPCRD...8.1147M">1979JPCRD...8.1147M</a>. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1063%2F1.555614">10.1063/1.555614</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/0047-2689">0047-2689</a>.</li> <li>McQuarrie DA & Rock PA 1987, <i>General chemistry</i>, 3rd ed., WH Freeman, New York</li> <li>Mendeléeff DI 1897, <i>The Principles of Chemistry</i>, vol. 2, 5th ed., trans. G Kamensky, AJ Greenaway (ed.), Longmans, Green & Co., London</li> <li>Mercier, R.; Douglade, J. (1982-06-15). "Structure cristalline d'un oxysulfate d'arsenic(III) As2O(SO4)2 (ou As2O3.2SO3)". <i>Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry</i>. 38 (6): 1731–1735. <a href="/facts/Bibcode_(identifier)/9HtdQSGB">Bibcode</a>:<a href="https://ui.adsabs.harvard.edu/abs/1982AcCrB..38.1731M">1982AcCrB..38.1731M</a>. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1107%2FS0567740882007055">10.1107/S0567740882007055</a>.</li> <li>Metcalfe HC, Williams JE & Castka JF 1966, <i>Modern chemistry</i>, 3rd ed., Holt, Rinehart and Winston, New York</li> <li>Mikulec, F.V.; Kirtland, J.D.; Sailor, M.J. (2002-01-04). "Explosive Nanocrystalline Porous Silicon and Its Use in Atomic Emission Spectroscopy". <i>Advanced Materials</i>. 14 (1). Wiley: 38–41. <a href="/facts/Bibcode_(identifier)/9HtdQSGB">Bibcode</a>:<a href="https://ui.adsabs.harvard.edu/abs/2002AdM....14...38M">2002AdM....14...38M</a>. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1002%2F1521-4095%2820020104%2914%3A1%3C38%3A%3Aaid-adma38%3E3.0.co%3B2-z">10.1002/1521-4095(20020104)14:1<38::aid-adma38>3.0.co;2-z</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/0935-9648">0935-9648</a>.</li> <li>Moss TS 1952, <i>Photoconductivity in the Elements</i>, London, Butterworths</li> <li>Mott NF & Davis EA 2012, 'Electronic Processes in Non-Crystalline Materials', 2nd ed., Oxford University Press, Oxford, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 978-0-19-964533-6</li> <li>Nakao, Yukimichi (1992). "Dissolution of noble metals in halogen–halide–polar organic solvent systems". <i>Journal of the Chemical Society, Chemical Communications</i> (5): 426–427. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1039%2FC39920000426">10.1039/C39920000426</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/0022-4936">0022-4936</a>.</li> <li>Nemodruk AA & Karalova ZK 1969, <i>Analytical chemistry of boron</i>, R Kondor trans., Ann Arbor Humphrey Science, Ann Arbor, Michigan</li> <li><i>New Scientist</i> 1975, 'Chemistry on the islands of stability', 11 Sep, p. 574, ISSN 1032-1233</li> <li>Noddack, Ida (1934-09-15). "Über das Element 93". <i>Angewandte Chemie</i>. 47 (37): 653–655. <a href="/facts/Bibcode_(identifier)/9HtdQSGB">Bibcode</a>:<a href="https://ui.adsabs.harvard.edu/abs/1934AngCh..47..653N">1934AngCh..47..653N</a>. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1002%2Fange.19340473707">10.1002/ange.19340473707</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/0044-8249">0044-8249</a>.</li> <li>Olechna, Doris J.; Knox, Robert S. (1965-11-01). "Energy-Band Structure of Selenium Chains". <i>Physical Review</i>. 140 (3A): A986 – A993. <a href="/facts/Bibcode_(identifier)/9HtdQSGB">Bibcode</a>:<a href="https://ui.adsabs.harvard.edu/abs/1965PhRv..140..986O">1965PhRv..140..986O</a>. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1103%2FPhysRev.140.A986">10.1103/PhysRev.140.A986</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/0031-899X">0031-899X</a>.</li> <li>Orton JW 2004, <i>The story of semiconductors</i>, Oxford University, Oxford, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 0-19-853083-8</li> <li>Parish RV 1977, <i>The metallic elements</i>, Longman, London</li> <li>Partington JR 1944, <i>A text-book of inorganic chemistry</i>, 5th ed., Macmillan & Co., London</li> <li>Pauling L 1988, <i><a href="https://books.google.com/books?id=EpxSzteNvMYC&pg=PA183">General chemistry</a></i>, Dover Publications, NY, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 0-486-65622-5</li> <li>Perkins D 1998, <i>Mineralogy</i>, Prentice Hall Books, Upper Saddle River, New Jersey, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 0-02-394501-X</li> <li>Pottenger FM & Bowes EE 1976, <i>Fundamentals of chemistry</i>, Scott, Foresman and Co., Glenview, Illinois</li> <li>Qin, Jiaqian; Nishiyama, Norimasa; Ohfuji, Hiroaki; Shinmei, Toru; Lei, Li; He, Duanwei; Irifune, Tetsuo (2012). "Polycrystalline γ-boron: As hard as polycrystalline cubic boron nitride". <i>Scripta Materialia</i>. 67 (3): 257–260. <a href="/facts/ArXiv_(identifier)/H6EtgnBe">arXiv</a>:<a href="https://arxiv.org/abs/1203.1748">1203.1748</a>. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1016%2Fj.scriptamat.2012.04.032">10.1016/j.scriptamat.2012.04.032</a>.</li> <li>Rao, C.N.R.; Ganguly, P. (1986). "A new criterion for the metallicity of elements". <i>Solid State Communications</i>. 57 (1): 5–6. <a href="/facts/Bibcode_(identifier)/9HtdQSGB">Bibcode</a>:<a href="https://ui.adsabs.harvard.edu/abs/1986SSCom..57....5R">1986SSCom..57....5R</a>. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1016%2F0038-1098%2886%2990659-9">10.1016/0038-1098(86)90659-9</a>.</li> <li>Rao KY 2002, <a href="https://books.google.com/books?id=BfyWUnv_-rEC"><i>Structural chemistry of glasses</i></a>, Elsevier, Oxford, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 0-08-043958-6</li> <li>Raub CJ & Griffith WP 1980, 'Osmium and sulphur', in <i>Gmelin handbook of inorganic chemistry</i>, 8th ed., 'Os, Osmium: Supplement', K Swars (ed.), system no. 66, Springer-Verlag, Berlin, pp. 166–170, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 3-540-93420-0</li> <li>Ravindran, P.; Fast, Lars; Korzhavyi, P. A.; Johansson, B.; Wills, J.; Eriksson, O. (1998-11-01). "Density functional theory for calculation of elastic properties of orthorhombic crystals: Application to TiSi2". <i>Journal of Applied Physics</i>. 84 (9): 4891–4904. <a href="/facts/Bibcode_(identifier)/9HtdQSGB">Bibcode</a>:<a href="https://ui.adsabs.harvard.edu/abs/1998JAP....84.4891R">1998JAP....84.4891R</a>. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1063%2F1.368733">10.1063/1.368733</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/0021-8979">0021-8979</a>.</li> <li>Reynolds WN 1969, <i>Physical properties of graphite</i>, Elsevier, Amsterdam</li> <li>Rochow EG 1966, <i>The metalloids</i>, DC Heath and Company, Boston</li> <li>Rock PA & Gerhold GA 1974, <i>Chemistry: Principles and applications</i>, WB Saunders, Philadelphia</li> <li>Russell JB 1981, <i>General chemistry</i>, McGraw-Hill, Auckland</li> <li>Russell AM & Lee KL 2005, <a href="https://books.google.com/books?id=fIu58uZTE-gC"><i>Structure-property relations in nonferrous metals</i></a>, Wiley-Interscience, New York, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 0-471-64952-X</li> <li>Sacks O 2001, <i>Uncle Tungsten: Memories of a chemical boyhood</i>, Alfred A Knopf, New York, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 0-375-40448-1</li> <li>Sanderson RT 1960, <i>Chemical periodicity</i>, Reinhold Publishing, New York</li> <li>Sanderson RT 1967, <i>Inorganic chemistry</i>, Reinhold, New York</li> <li>Sanderson K 2012, 'Stinky rocks hide Earth's only haven for natural fluorine', <i>Nature News</i>, July, <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1038%2Fnature.2012.10992">10.1038/nature.2012.10992</a></li> <li>Schaefer JC 1968, 'Boron' in CA Hampel (ed.), <i>The encyclopedia of the chemical elements</i>, Reinhold, New York, pp. 73–81</li> <li>Sidgwick NV 1950, <i>The chemical elements and their compounds</i>, vol. 1, Clarendon, Oxford</li> <li>Sidorov, T. A. (1960). "The connection between structural oxides and their tendency to glass formation". <i>Glass and Ceramics</i>. 17 (11): 599–603. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1007%2FBF00670116">10.1007/BF00670116</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/0361-7610">0361-7610</a>.</li> <li>Sisler HH 1973, <i>Electronic structure, properties, and the periodic law</i>, Van Nostrand, New York</li> <li>Slezak 2014, <a href="https://www.newscientist.com/article/dn24886-natural-ball-lightning-probed-for-the-first-time/">'Natural ball lightning probed for the first time'</a>, <i>New Scientist</i>, 16 January</li> <li>Slough W 1972, 'Discussion of session 2b: Crystal structure and bond mechanism of metallic compounds', in O Kubaschewski (ed.), <i>Metallurgical chemistry, proceedings of a symposium held at Brunel University and the National Physical Laboratory on the 14, 15 and 16 July 1971</i>, Her Majesty's Stationery Office [for the] National Physical Laboratory, London</li> <li>Slyh JA 1955, 'Graphite', in JF Hogerton & RC Grass (eds), <i>Reactor handbook: Materials</i>, US Atomic Energy Commission, McGraw Hill, New York, pp. 133‒154</li> <li>Smith A 1921, <i>General chemistry for colleges</i>, 2nd ed., Century, New York</li> <li>Sneed MC 1954, <i>General college chemistry</i>, Van Nostrand, New York</li> <li>Sommer, A. (1943). "Alloys of Gold with Alkali Metals". <i>Nature</i>. 152 (3851): 215. <a href="/facts/Bibcode_(identifier)/9HtdQSGB">Bibcode</a>:<a href="https://ui.adsabs.harvard.edu/abs/1943Natur.152..215S">1943Natur.152..215S</a>. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1038%2F152215a0">10.1038/152215a0</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/0028-0836">0028-0836</a>.</li> <li>Soverna S 2004, <a href="https://web.archive.org/web/20070329222141/http://www.gsi.de/informationen/wti/library/scientificreport2003/files/167.pdf">'Indication for a gaseous element 112'</a>, in U Grundinger (ed.), <i>GSI Scientific Report 2003</i>, GSI Report 2004-1, p. 187, ISSN 0174-0814</li> <li>Stoker HS 2010, <a href="https://books.google.com/books?id=Yig6eLv_O4MC"><i>General, organic, and biological chemistry</i></a>, 5th ed., Brooks/Cole, Cengage Learning, Belmont CA, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 0-495-83146-8</li> <li>Stoye, E., 2014, <a href="https://www.chemistryworld.com/news/iridium-forms-compound-in-9-oxidation-state-/7889.article">'Iridium forms compound in +9 oxidation state'</a>, <i>Chemistry World</i>, 22 October 2014</li> <li>Sun, Haiyan; Xu, Zhen; Gao, Chao (2013-05-14). "Multifunctional, Ultra-Flyweight, Synergistically Assembled Carbon Aerogels". <i>Advanced Materials</i>. 25 (18): 2554–2560. <a href="/facts/Bibcode_(identifier)/9HtdQSGB">Bibcode</a>:<a href="https://ui.adsabs.harvard.edu/abs/2013AdM....25.2554S">2013AdM....25.2554S</a>. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1002%2Fadma.201204576">10.1002/adma.201204576</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/0935-9648">0935-9648</a>. <a href="/facts/PMID_(identifier)/JlHAvMHt">PMID</a> <a href="https://pubmed.ncbi.nlm.nih.gov/23418099">23418099</a>.</li> <li>Rao, R. V. G. Sundara (1950). "Elastic constants of orthorhombic sulphur". <i>Proceedings of the Indian Academy of Sciences - Section A</i>. 32 (4): 275-278. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1007%2FBF03170831">10.1007/BF03170831</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/0370-0089">0370-0089</a>.</li> <li>Sundara Rao RVG 1954, 'Erratum to: Elastic constants of orthorhombic sulphur', <i>Proceedings of the Indian Academy of Sciences, Section A</i>, vol. 40, no. 3, p. 151</li> <li>Swalin RA 1962, <i>Thermodynamics of solids</i>, John Wiley & Sons, New York</li> <li>Tilley RJD 2004, <i>Understanding solids: The science of materials</i>, 4th ed., John Wiley, New York</li> <li>Walker JD, Newman MC & Enache M 2013, <i>Fundamental QSARs for metal ions</i>, CRC Press, Boca Raton, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 978-1-4200-8434-4</li> <li>White, Mary Anne; Cerqueira, Anthony B.; Whitman, Catherine A.; Johnson, Michel B.; Ogitsu, Tadashi (2015-03-16). "Determination of Phase Stability of Elemental Boron". <i>Angewandte Chemie International Edition</i>. 54 (12): 3626–3629. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1002%2Fanie.201409169">10.1002/anie.201409169</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/1433-7851">1433-7851</a>. <a href="/facts/PMID_(identifier)/JlHAvMHt">PMID</a> <a href="https://pubmed.ncbi.nlm.nih.gov/25619645">25619645</a>.</li> <li>Wiberg N 2001, <i><a href="https://books.google.com/books?id=Mtth5g59dEIC">Inorganic chemistry</a></i>, Academic Press, San Diego, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 0-12-352651-5</li> <li>Wickleder, M. S.; Pley, M.; Büchner, O. (2006). "Sulfates of Precious Metals: Fascinating Chemistry of Potential Materials". <i>Zeitschrift für anorganische und allgemeine Chemie</i>. 632 (12–13): 2080. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1002%2Fzaac.200670009">10.1002/zaac.200670009</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/0044-2313">0044-2313</a>.</li> <li>Wickleder MS 2007, 'Chalcogen-oxygen chemistry', in FA Devillanova (ed.), <i>Handbook of chalcogen chemistry: new perspectives in sulfur, selenium and tellurium</i>, RSC, Cambridge, pp. 344–377, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 978-0-85404-366-8</li> <li>Wilson JR 1965, 'The structure of liquid metals and alloys', <i>Metallurgical reviews</i>, vol. 10, p. 502</li> <li>Wilson AH 1966, <i>Thermodynamics and statistical mechanics</i>, Cambridge University, Cambridge</li> <li>Witczak Z, Goncharova VA & Witczak PP 2000, 'Irreversible effect of hydrostatic pressure on the elastic properties of polycrystalline tellurium', in MH Manghnani, WJ Nellis & MF Nicol (eds), <i>Science and technology of high pressure: Proceedings of the International Conference on High Pressure Science and Technology (AIRAPT-17)</i>, Honolulu, Hawaii, 25‒30 July 1999, vol. 2, Universities Press, Hyderabad, pp. 822‒825, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 81-7371-339-1</li> <li>Witt SF 1991, <a href="https://www.osha.gov/publications/hib19980309">'Dimethylmercury'</a>, <i>Occupational Safety & Health Administration Hazard Information Bulletin</i>, US Department of Labor, February 15, accessed 8 May 2015</li> <li>Wittenberg, Layton J.; DeWitt, Robert (1972-05-01). "Volume Contraction During Melting; Emphasis on Lanthanide and Actinide Metals". <i>The Journal of Chemical Physics</i>. 56 (9): 4526–4533. <a href="/facts/Bibcode_(identifier)/9HtdQSGB">Bibcode</a>:<a href="https://ui.adsabs.harvard.edu/abs/1972JChPh..56.4526W">1972JChPh..56.4526W</a>. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1063%2F1.1677899">10.1063/1.1677899</a>. <a href="/facts/ISSN_(identifier)/DPAflDvU">ISSN</a> <a href="https://search.worldcat.org/issn/0021-9606">0021-9606</a>.</li> <li>Wulfsberg G 2000, <i><a href="https://books.google.com/books?id=hpWzxTnQH14C&pg=PA620">Inorganic chemistry</a></i>, University Science Books, Sausalito CA, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 1-891389-01-7</li> <li>Young RV & Sessine S (eds) 2000, <i>World of chemistry</i>, Gale Group, Farmington Hills, Michigan</li> <li>Zhigal'skii GP & Jones BK 2003, <i>Physical properties of thin metal films</i>, Taylor & Francis, London, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 0-415-28390-6</li> <li>Zuckerman & Hagen (eds) 1991, <i>Inorganic reactions and methods, vol, 5: The formation of bonds to group VIB (<a href="/facts/Oxygen/acyn6o8r">O</a>, <a href="/facts/Sulfur/IK0amTfM">S</a>, <a href="/facts/Selenium/k975NApC">Se</a>, <a href="/facts/Tellurium/v7QvfIvS">Te</a>, <a href="/facts/Polonium/G4rzsyjP">Po</a>) elements</i> (part 1), VCH Publishers, Deerfield Beach, Fla, <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 0-89573-250-5</li></ul> <h2 id="references">References</h2> <ol> <li id="fn:1"><p>For example: Brinkley[2] writes that boron has weakly nonmetallic properties. Glinka[3] describes silicon as a weak nonmetal. Eby et al.[4] discuss the weak chemical behaviour of the elements close to the metal-nonmetal borderline. Booth and Bloom[5] say "A period represents a stepwise change from elements strongly metallic to weakly metallic to weakly nonmetallic to strongly nonmetallic, and then, at the end, to an abrupt cessation of almost all chemical properties ...". Cox[6] notes "nonmetallic elements close to the metallic borderline (Si, Ge, As, Sb, Se, Te) show less tendency to anionic behaviour and are sometimes called metalloids." <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li> <li id="fn:2"><p>See, for example, Huheey, Keiter & Keiter[7] who classify Ge and Sb as post-transition metals. <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li> <li id="fn:3"><p>At standard pressure and temperature, for the elements in their most thermodynamically stable forms, unless otherwise noted <a href="#fnref:3" class="footnote-back-ref">↩</a></p></li> <li id="fn:4"><p>Kneen, Rogers & Simpson, 1972, p. 263. Columns 2 (metals) and 4 (nonmetals) are sourced from this reference unless otherwise indicated. <a href="#fnref:4" class="footnote-back-ref">↩</a></p></li> <li id="fn:5"><p>Kneen, Rogers & Simpson, 1972, p. 263. Columns 2 (metals) and 4 (nonmetals) are sourced from this reference unless otherwise indicated. <a href="#fnref:5" class="footnote-back-ref">↩</a></p></li> <li id="fn:6"><p>Russell & Lee 2005, p. 147 <a href="#fnref:6" class="footnote-back-ref">↩</a></p></li> <li id="fn:7"><p>Rochow 1966, p. 4 <a href="#fnref:7" class="footnote-back-ref">↩</a></p></li> <li id="fn:8"><p>Pottenger & Bowes 1976, p. 138 <a href="#fnref:8" class="footnote-back-ref">↩</a></p></li> <li id="fn:9"><p>Askeland, Fulay & Wright 2011, p. 806 <a href="#fnref:9" class="footnote-back-ref">↩</a></p></li> <li id="fn:10"><p>Born & Wolf 1999, p. 746 <a href="#fnref:10" class="footnote-back-ref">↩</a></p></li> <li id="fn:11"><p>Lagrenaudie 1953 <a href="#fnref:11" class="footnote-back-ref">↩</a></p></li> <li id="fn:12"><p>Rochow 1966, pp. 23, 25 <a href="#fnref:12" class="footnote-back-ref">↩</a></p></li> <li id="fn:13"><p>Burakowski & Wierzchoń 1999, p. 336 <a href="#fnref:13" class="footnote-back-ref">↩</a></p></li> <li id="fn:14"><p>Olechna & Knox 1965, pp. A991‒92 <a href="#fnref:14" class="footnote-back-ref">↩</a></p></li> <li id="fn:15"><p>Stoker 2010, p. 62 <a href="#fnref:15" class="footnote-back-ref">↩</a></p></li> <li id="fn:16"><p>Chang 2002, p. 304. Chang speculates that the melting point of francium would be about 23 °C. <a href="#fnref:16" class="footnote-back-ref">↩</a></p></li> <li id="fn:17"><p>Copernicium is reported to be the only metal known to be a gas at room temperature.[20] <a href="/wiki/Copernicium" target="_blank">/wiki/Copernicium</a> <a href="#fnref:17" class="footnote-back-ref">↩</a></p></li> <li id="fn:18"><p>Rochow 1966, p. 4 <a href="#fnref:18" class="footnote-back-ref">↩</a></p></li> <li id="fn:19"><p>Hunt 2000, p. 256 <a href="#fnref:19" class="footnote-back-ref">↩</a></p></li> <li id="fn:20"><p>Sisler 1973, p. 89 <a href="#fnref:20" class="footnote-back-ref">↩</a></p></li> <li id="fn:21"><p>Hérold 2006, pp. 149–150 <a href="#fnref:21" class="footnote-back-ref">↩</a></p></li> <li id="fn:22"><p>Russell & Lee 2005 <a href="#fnref:22" class="footnote-back-ref">↩</a></p></li> <li id="fn:23"><p>Whether polonium is ductile or brittle is unclear. It is predicted to be ductile based on its calculated elastic constants.[25] It has a simple cubic crystalline structure. Such a structure has few slip systems and "leads to very low ductility and hence low fracture resistance".[26] <a href="/wiki/Young%27s_modulus#Relation_among_elastic_constants" target="_blank">/wiki/Young%27s_modulus#Relation_among_elastic_constants</a> <a href="#fnref:23" class="footnote-back-ref">↩</a></p></li> <li id="fn:24"><p>McQuarrie & Rock 1987, p. 85 <a href="#fnref:24" class="footnote-back-ref">↩</a></p></li> <li id="fn:25"><p>Carbon as exfoliated (expanded) graphite,[28] and as metre-long carbon nanotube wire;[29] phosphorus as white phosphorus (soft as wax, pliable and can be cut with a knife, at room temperature);[30] sulfur as plastic sulfur;[31] and selenium as selenium wires.[32] <a href="/wiki/Graphite#Expanded_graphite" target="_blank">/wiki/Graphite#Expanded_graphite</a> <a href="#fnref:25" class="footnote-back-ref">↩</a></p></li> <li id="fn:26"><p>For polycrystalline forms of the elements unless otherwise noted. Determining Poisson's ratio accurately is a difficult proposition and there could be considerable uncertainty in some reported values.[33] <a href="#fnref:26" class="footnote-back-ref">↩</a></p></li> <li id="fn:27"><p>Beryllium has the lowest known value (0.0476) among elemental metals; indium and thallium each have the highest known value (0.46). Around one third show a value ≥ 0.33.[34] <a href="#fnref:27" class="footnote-back-ref">↩</a></p></li> <li id="fn:28"><p>Boron 0.13;[35] silicon 0.22;[36] germanium 0.278;[37] amorphous arsenic 0.27;[38] antimony 0.25;[39] tellurium ~0.2.[40] <a href="#fnref:28" class="footnote-back-ref">↩</a></p></li> <li id="fn:29"><p>Graphitic carbon 0.25;[41] [diamond 0.0718];[42] black phosphorus 0.30;[43] sulfur 0.287;[44] amorphous selenium 0.32;[45] amorphous iodine ~0.[46] <a href="#fnref:29" class="footnote-back-ref">↩</a></p></li> <li id="fn:30"><p>Donohoe 1982; Russell & Lee 2005 <a href="#fnref:30" class="footnote-back-ref">↩</a></p></li> <li id="fn:31"><p>Gupta et al. 2005, p. 502 <a href="#fnref:31" class="footnote-back-ref">↩</a></p></li> <li id="fn:32"><p>Walker, Newman & Enache 2013, p. 25 <a href="#fnref:32" class="footnote-back-ref">↩</a></p></li> <li id="fn:33"><p>Wiberg 2001, p. 143 <a href="#fnref:33" class="footnote-back-ref">↩</a></p></li> <li id="fn:34"><p>Batsanov & Batsanov 2012, p. 275 <a href="#fnref:34" class="footnote-back-ref">↩</a></p></li> <li id="fn:35"><p>Clementi & Raimondi 1963; Clementi, Raimondi & Reinhardt 1967 <a href="#fnref:35" class="footnote-back-ref">↩</a></p></li> <li id="fn:36"><p>Addison 1964; Donohoe 1982 <a href="#fnref:36" class="footnote-back-ref">↩</a></p></li> <li id="fn:37"><p>At atmospheric pressure, for elements with known structures <a href="/wiki/Atmospheric_pressure" target="_blank">/wiki/Atmospheric_pressure</a> <a href="#fnref:37" class="footnote-back-ref">↩</a></p></li> <li id="fn:38"><p>Vernon 2013, p. 1704 <a href="#fnref:38" class="footnote-back-ref">↩</a></p></li> <li id="fn:39"><p>Parish 1977, pp. 34, 48, 112, 142, 156, 178 <a href="#fnref:39" class="footnote-back-ref">↩</a></p></li> <li id="fn:40"><p>Emsley 2001, p. 12 <a href="#fnref:40" class="footnote-back-ref">↩</a></p></li> <li id="fn:41"><p>Emsley 2001, p. 12 <a href="#fnref:41" class="footnote-back-ref">↩</a></p></li> <li id="fn:42"><p>Russell 1981, p. 628 <a href="#fnref:42" class="footnote-back-ref">↩</a></p></li> <li id="fn:43"><p>The Goldhammer-Herzfeld criterion is a ratio that compares the force holding an individual atom's valence electrons in place with the forces, acting on the same electrons, arising from interactions between the atoms in the solid or liquid element. When the interatomic forces are greater than or equal to the atomic force, valence electron itinerancy is indicated. Metallic behaviour is then predicted.[58] Otherwise nonmetallic behaviour is anticipated. The Goldhammer-Herzfeld criterion is based on classical arguments.[59] It nevertheless offers a relatively simple first order rationalization for the occurrence of metallic character among the elements.[60] <a href="/wiki/Karl_Herzfeld" target="_blank">/wiki/Karl_Herzfeld</a> <a href="#fnref:43" class="footnote-back-ref">↩</a></p></li> <li id="fn:44"><p>Edwards & Sienko 1983, p. 691 <a href="#fnref:44" class="footnote-back-ref">↩</a></p></li> <li id="fn:45"><p>Edwards et al. 2010 <a href="#fnref:45" class="footnote-back-ref">↩</a></p></li> <li id="fn:46"><p>Metals have electrical conductivity values of from 6.9 × 103 S•cm−1 for manganese to 6.3 × 105 for silver.[63] <a href="/wiki/Manganese" target="_blank">/wiki/Manganese</a> <a href="#fnref:46" class="footnote-back-ref">↩</a></p></li> <li id="fn:47"><p>Choppin & Johnsen 1972, p. 351 <a href="#fnref:47" class="footnote-back-ref">↩</a></p></li> <li id="fn:48"><p>Metalloids have electrical conductivity values of from 1.5 × 10−6 S•cm−1 for boron to 3.9 × 104 for arsenic.[65] If selenium is included as a metalloid the applicable conductivity range would start from ~10−9 to 10−12 S•cm−1.[66][67][68] <a href="/wiki/Arsenic" target="_blank">/wiki/Arsenic</a> <a href="#fnref:48" class="footnote-back-ref">↩</a></p></li> <li id="fn:49"><p>Nonmetals have electrical conductivity values of from ~10−18 S•cm−1 for the elemental gases to 3 × 104 in graphite.[69] <a href="#fnref:49" class="footnote-back-ref">↩</a></p></li> <li id="fn:50"><p>Rao & Ganguly 1986 <a href="#fnref:50" class="footnote-back-ref">↩</a></p></li> <li id="fn:51"><p>Mott and Davis[71] note however that 'liquid europium has a negative temperature coefficient of resistance' i.e. that conductivity increases with rising temperature <a href="#fnref:51" class="footnote-back-ref">↩</a></p></li> <li id="fn:52"><p>Edwards & Sienko 1983, p. 691 <a href="#fnref:52" class="footnote-back-ref">↩</a></p></li> <li id="fn:53"><p>Antia 1998 <a href="#fnref:53" class="footnote-back-ref">↩</a></p></li> <li id="fn:54"><p>Cverna 2002, p.1 <a href="#fnref:54" class="footnote-back-ref">↩</a></p></li> <li id="fn:55"><p>McQuarrie & Rock 1987, p. 85 <a href="#fnref:55" class="footnote-back-ref">↩</a></p></li> <li id="fn:56"><p>Cordes & Scaheffer 1973, p. 79 <a href="#fnref:56" class="footnote-back-ref">↩</a></p></li> <li id="fn:57"><p>Hill & Holman 2000, p. 42 <a href="#fnref:57" class="footnote-back-ref">↩</a></p></li> <li id="fn:58"><p>Tilley 2004, p. 487 <a href="#fnref:58" class="footnote-back-ref">↩</a></p></li> <li id="fn:59"><p>At or near room temperature <a href="#fnref:59" class="footnote-back-ref">↩</a></p></li> <li id="fn:60"><p>Russell & Lee 2005, p. 466 <a href="#fnref:60" class="footnote-back-ref">↩</a></p></li> <li id="fn:61"><p>Orton 2004, pp. 11–12 <a href="#fnref:61" class="footnote-back-ref">↩</a></p></li> <li id="fn:62"><p>Zhigal'skii & Jones 2003, p. 66: 'Bismuth, antimony, arsenic and graphite are considered to be semimetals ... In bulk semimetals ... the resistivity will increase with temperature ... to give a positive temperature coefficient of resistivity ...' <a href="#fnref:62" class="footnote-back-ref">↩</a></p></li> <li id="fn:63"><p>Jauncey 1948, p. 500: 'Nonmetals mostly have negative temperature coefficients. For instance, carbon ... [has a] resistance [that] decreases with a rise in temperature. However, recent experiments on very pure graphite, which is a form of carbon, have shown that pure carbon in this form behaves similarly to metals in regard to its resistance.' <a href="#fnref:63" class="footnote-back-ref">↩</a></p></li> <li id="fn:64"><p>Reynolds 1969, pp. 91–92 <a href="#fnref:64" class="footnote-back-ref">↩</a></p></li> <li id="fn:65"><p>Wilson 1966, p. 260 <a href="#fnref:65" class="footnote-back-ref">↩</a></p></li> <li id="fn:66"><p>Wittenberg 1972, p. 4526 <a href="#fnref:66" class="footnote-back-ref">↩</a></p></li> <li id="fn:67"><p>Habashi 2003, p. 73 <a href="#fnref:67" class="footnote-back-ref">↩</a></p></li> <li id="fn:68"><p>Wilson 1966, p. 260 <a href="#fnref:68" class="footnote-back-ref">↩</a></p></li> <li id="fn:69"><p>Bailar et al. 1989, p. 742 <a href="#fnref:69" class="footnote-back-ref">↩</a></p></li> <li id="fn:70"><p>Cox 2004, p. 27 <a href="#fnref:70" class="footnote-back-ref">↩</a></p></li> <li id="fn:71"><p>Hiller & Herber 1960, inside front cover; p. 225 <a href="#fnref:71" class="footnote-back-ref">↩</a></p></li> <li id="fn:72"><p>Beveridge et al. 1997, p. 185 <a href="#fnref:72" class="footnote-back-ref">↩</a></p></li> <li id="fn:73"><p>Young & Sessine 2000, p. 849 <a href="#fnref:73" class="footnote-back-ref">↩</a></p></li> <li id="fn:74"><p>Bailar et al. 1989, p. 417 <a href="#fnref:74" class="footnote-back-ref">↩</a></p></li> <li id="fn:75"><p>Metcalfe, Williams & Castka 1966, p. 72 <a href="#fnref:75" class="footnote-back-ref">↩</a></p></li> <li id="fn:76"><p>Chang 1994, p. 311 <a href="#fnref:76" class="footnote-back-ref">↩</a></p></li> <li id="fn:77"><p>Pauling 1988, p. 183 <a href="#fnref:77" class="footnote-back-ref">↩</a></p></li> <li id="fn:78"><p>Mann et al. 2000, p. 2783 <a href="#fnref:78" class="footnote-back-ref">↩</a></p></li> <li id="fn:79"><p>Chedd[94] defines metalloids as having electronegativity values of 1.8 to 2.2 (Allred-Rochow scale). He included boron, silicon, germanium, arsenic, antimony, tellurium, polonium and astatine in this category. In reviewing Chedd's work, Adler[95] described this choice as arbitrary, given other elements have electronegativities in this range, including copper, silver, phosphorus, mercury, and bismuth. He went on to suggest defining a metalloid simply as, 'a semiconductor or semimetal' and 'to have included the interesting materials bismuth and selenium in the book'. <a href="#fnref:79" class="footnote-back-ref">↩</a></p></li> <li id="fn:80"><p>Young & Sessine 2000, p. 849 <a href="#fnref:80" class="footnote-back-ref">↩</a></p></li> <li id="fn:81"><p>Hultgren 1966, p. 648 <a href="#fnref:81" class="footnote-back-ref">↩</a></p></li> <li id="fn:82"><p>Bassett et al. 1966, p. 602 <a href="#fnref:82" class="footnote-back-ref">↩</a></p></li> <li id="fn:83"><p>Phosphorus is known to form a carbide in thin films. <a href="#fnref:83" class="footnote-back-ref">↩</a></p></li> <li id="fn:84"><p>Rochow 1966, p. 34 <a href="#fnref:84" class="footnote-back-ref">↩</a></p></li> <li id="fn:85"><p>Martienssen & Warlimont 2005, p. 257 <a href="#fnref:85" class="footnote-back-ref">↩</a></p></li> <li id="fn:86"><p>Sidorov 1960 <a href="#fnref:86" class="footnote-back-ref">↩</a></p></li> <li id="fn:87"><p>Brasted 1974, p. 814 <a href="#fnref:87" class="footnote-back-ref">↩</a></p></li> <li id="fn:88"><p>Rochow 1966, p. 4 <a href="#fnref:88" class="footnote-back-ref">↩</a></p></li> <li id="fn:89"><p>Atkins 2006 et al., pp. 8, 122–23 <a href="#fnref:89" class="footnote-back-ref">↩</a></p></li> <li id="fn:90"><p>Rao 2002, p. 22 <a href="#fnref:90" class="footnote-back-ref">↩</a></p></li> <li id="fn:91"><p>See, for example, the sulfates of the transition metals,[104] the lanthanides[105] and the actinides.[106] <a href="/wiki/Transition_metal" target="_blank">/wiki/Transition_metal</a> <a href="#fnref:91" class="footnote-back-ref">↩</a></p></li> <li id="fn:92"><p>Sulfates of osmium have not been characterized with any great degree of certainty.[107] <a href="#fnref:92" class="footnote-back-ref">↩</a></p></li> <li id="fn:93"><p>Common metalloids: Boron is reported to be capable of forming an oxysulfate (BO)2SO4,[108] a bisulfate B(HSO4)3[109] and a sulfate B2(SO4)3.[110] The existence of a sulfate has been disputed.[111] In light of the existence of silicon phosphate, a silicon sulfate might also exist.[112] Germanium forms an unstable sulfate Ge(SO4)2 (d 200 °C).[113] Arsenic forms oxide sulfates As2O(SO4)2 (= As2O3.2SO3)[114] and As2(SO4)3 (= As2O3.3SO3).[115] Antimony forms a sulfate Sb2(SO4)3 and an oxysulfate (SbO)2SO4.[116] Tellurium forms an oxide sulfate Te2O3(SO)4.[117] Less common: Polonium forms a sulfate Po(SO4)2.[118] It has been suggested that the astatine cation forms a weak complex with sulfate ions in acidic solutions.[119] <a href="#fnref:93" class="footnote-back-ref">↩</a></p></li> <li id="fn:94"><p>Hydrogen forms hydrogen sulfate H2SO4. Carbon forms (a blue) graphite hydrogen sulfate C+24HSO–4 • 2.4H2SO4.[120] Nitrogen forms nitrosyl hydrogen sulfate (NO)HSO4 and nitronium (or nitryl) hydrogen sulfate (NO2)HSO4.[121] There are indications of a basic sulfate of selenium SeO2.SO3 or SeO(SO4).[122] Iodine forms a polymeric yellow sulfate (IO)2SO4.[123] <a href="/wiki/Hydrogen_sulfate" target="_blank">/wiki/Hydrogen_sulfate</a> <a href="#fnref:94" class="footnote-back-ref">↩</a></p></li> <li id="fn:95"><p>Holtzclaw, Robinson & Odom 1991, pp. 706–07; Keenan, Kleinfelter & Wood 1980, pp. 693–95 <a href="#fnref:95" class="footnote-back-ref">↩</a></p></li> <li id="fn:96"><p>layer-lattice types often reversibly so <a href="#fnref:96" class="footnote-back-ref">↩</a></p></li> <li id="fn:97"><p>Kneen, Rogers & Simpson 1972, p. 278 <a href="#fnref:97" class="footnote-back-ref">↩</a></p></li> <li id="fn:98"><p>Heslop & Robinson 1963, p. 417 <a href="#fnref:98" class="footnote-back-ref">↩</a></p></li> <li id="fn:99"><p>Rochow 1966, pp. 28–29 <a href="#fnref:99" class="footnote-back-ref">↩</a></p></li> <li id="fn:100"><p>Bagnall 1966, pp. 108, 120; Lidin 1996, passim <a href="#fnref:100" class="footnote-back-ref">↩</a></p></li> <li id="fn:101"><p>Smith 1921, p. 295; Sidgwick 1950, pp. 605, 608; Dunstan 1968, pp. 408, 438 <a href="#fnref:101" class="footnote-back-ref">↩</a></p></li> <li id="fn:102"><p>Smith 1921, p. 295; Sidgwick 1950, pp. 605, 608; Dunstan 1968, pp. 408, 438 <a href="#fnref:102" class="footnote-back-ref">↩</a></p></li> <li id="fn:103"><p>Dunstan 1968, pp. 312, 408 <a href="#fnref:103" class="footnote-back-ref">↩</a></p></li> <li id="fn:104"><p>Based on a table of the elemental composition of the biosphere, and lithosphere (crust, atmosphere, and seawater) in Georgievskii,[131] and the masses of the crust and hydrosphere give in Lide and Frederikse.[132] The mass of the biosphere is negligible, having a mass of about one billionth that of the lithosphere.[citation needed] "The oceans constitute about 98 percent of the hydrosphere, and thus the average composition of the hydrosphere is, for all practical purposes, that of seawater."[133] <a href="#fnref:104" class="footnote-back-ref">↩</a></p></li> <li id="fn:105"><p>Perkins 1998, p. 350 <a href="#fnref:105" class="footnote-back-ref">↩</a></p></li> <li id="fn:106"><p>Hydrogen gas is produced by some bacteria and algae and is a natural component of flatus. It can be found in the Earth's atmosphere at a concentration of 1 part per million by volume. <a href="/wiki/Algae" target="_blank">/wiki/Algae</a> <a href="#fnref:106" class="footnote-back-ref">↩</a></p></li> <li id="fn:107"><p>Fluorine can be found in its elemental form, as an occlusion in the mineral antozonite[135] <a href="/wiki/Antozonite" target="_blank">/wiki/Antozonite</a> <a href="#fnref:107" class="footnote-back-ref">↩</a></p></li> <li id="fn:108"><p>Brown et al. 2009, p. 137 <a href="#fnref:108" class="footnote-back-ref">↩</a></p></li> <li id="fn:109"><p>Bresica et al. 1975, p. 137 <a href="#fnref:109" class="footnote-back-ref">↩</a></p></li> <li id="fn:110"><p>Jansen 2005 <a href="#fnref:110" class="footnote-back-ref">↩</a></p></li> <li id="fn:111"><p>Russell & Lee 2005, p. 246 <a href="#fnref:111" class="footnote-back-ref">↩</a></p></li> <li id="fn:112"><p>Russell & Lee 2005, p. 244–5 <a href="#fnref:112" class="footnote-back-ref">↩</a></p></li> <li id="fn:113"><p>Russell & Lee 2005, p. 246 <a href="#fnref:113" class="footnote-back-ref">↩</a></p></li> <li id="fn:114"><p>Donohoe 1982, pp. 191–196; Russell & Lee 2005, pp. 244–247 <a href="#fnref:114" class="footnote-back-ref">↩</a></p></li> <li id="fn:115"><p>Jackson 2000 <a href="#fnref:115" class="footnote-back-ref">↩</a></p></li> <li id="fn:116"><p>Stoye 2014 <a href="#fnref:116" class="footnote-back-ref">↩</a></p></li> <li id="fn:117"><p>Witt 1991; Endicott 1998 <a href="#fnref:117" class="footnote-back-ref">↩</a></p></li> <li id="fn:118"><p>Dumé 2003 <a href="#fnref:118" class="footnote-back-ref">↩</a></p></li> <li id="fn:119"><p>Benedict et al. 1946, p. 19 <a href="#fnref:119" class="footnote-back-ref">↩</a></p></li> <li id="fn:120"><p>In 1934, a team led by Enrico Fermi postulated that transuranic elements may have been produced as a result of bombarding uranium with neutrons, a finding which was widely accepted for a few years. In the same year Ida Noddack, a German scientist and subsequently a three-time Nobel prize nominee, criticised this assumption, writing "It is conceivable that the nucleus breaks up into several large fragments, which would of course be isotopes of known elements but would not be neighbors of the irradiated element."[147][emphasis added] In this, Noddak defied the understanding of the time without offering experimental proof or theoretical basis, but nevertheless presaged what would be known a few years later as nuclear fission. Her paper was generally ignored as, in 1925, she and two colleagues claimed to have discovered element 43, then proposed to be called masurium (later discovered in 1936 by Perrier and Segrè, and named technetium). Had Ida Noddack's paper been accepted it is likely that Germany would have had an atomic bomb and, 'the history of the world would have been [very] different.'[148] <a href="/wiki/Enrico_Fermi" target="_blank">/wiki/Enrico_Fermi</a> <a href="#fnref:120" class="footnote-back-ref">↩</a></p></li> <li id="fn:121"><p>Hecker, Siegfried S. (2000). "Plutonium and its alloys: from atoms to microstructure" (PDF). Los Alamos Science. 26: 290–335. Archived (PDF) from the original on February 24, 2009. Retrieved February 15, 2009. <a href="https://fas.org/sgp/othergov/doe/lanl/pubs/00818035.pdf" target="_blank">https://fas.org/sgp/othergov/doe/lanl/pubs/00818035.pdf</a> <a href="#fnref:121" class="footnote-back-ref">↩</a></p></li> <li id="fn:122"><p>Tsiovkin, Yu.Yu.; Lukoyanov, A.V.; Shorikov, A.O.; Tsiovkina, L.Yu.; Dyachenko, A.A.; Bystrushkin, V.B.; Korotin, M.A.; Anisimov, V.I.; Dremov, V.V. (2011). "Electrical resistivity of pure transuranium metals under pressure". Journal of Nuclear Materials. 413 (1): 41–46. Bibcode:2011JNuM..413...41T. doi:10.1016/j.jnucmat.2011.03.053. <a href="https://linkinghub.elsevier.com/retrieve/pii/S0022311511003369" target="_blank">https://linkinghub.elsevier.com/retrieve/pii/S0022311511003369</a> <a href="#fnref:122" class="footnote-back-ref">↩</a></p></li> <li id="fn:123"><p>Dalhouse University 2015; White et al. 2015 <a href="#fnref:123" class="footnote-back-ref">↩</a></p></li> <li id="fn:124"><p>DuPlessis 2007, p. 133 <a href="#fnref:124" class="footnote-back-ref">↩</a></p></li> <li id="fn:125"><p>Gösele & Lehmann 1994, p. 19 <a href="#fnref:125" class="footnote-back-ref">↩</a></p></li> <li id="fn:126"><p>Chen, Lee & Bosman 1994 <a href="#fnref:126" class="footnote-back-ref">↩</a></p></li> <li id="fn:127"><p>Kovalev et al. 2001, p. 068301-1 <a href="#fnref:127" class="footnote-back-ref">↩</a></p></li> <li id="fn:128"><p>Mikulec, Kirtland & Sailor 2002 <a href="#fnref:128" class="footnote-back-ref">↩</a></p></li> <li id="fn:129"><p>Kovalev et al. 2001, p. 068301-1 <a href="#fnref:129" class="footnote-back-ref">↩</a></p></li> <li id="fn:130"><p>DuPlessis 2007, p. 133 <a href="#fnref:130" class="footnote-back-ref">↩</a></p></li> <li id="fn:131"><p>Bychkov 2012, pp. 20–21; see also Lazaruk et al. 2007 <a href="#fnref:131" class="footnote-back-ref">↩</a></p></li> <li id="fn:132"><p>Slezak 2014 <a href="#fnref:132" class="footnote-back-ref">↩</a></p></li> <li id="fn:133"><p>Wiberg 2001, p. 758; see also Fraden 1951 <a href="#fnref:133" class="footnote-back-ref">↩</a></p></li> <li id="fn:134"><p>Sacks 2001, p. 204 <a href="#fnref:134" class="footnote-back-ref">↩</a></p></li> <li id="fn:135"><p>Sacks 2001, pp. 204–205 <a href="#fnref:135" class="footnote-back-ref">↩</a></p></li> <li id="fn:136"><p>Cerkovnik & Plesničar 2013, p. 7930 <a href="#fnref:136" class="footnote-back-ref">↩</a></p></li> <li id="fn:137"><p>Emsley 1994, p. 1910 <a href="#fnref:137" class="footnote-back-ref">↩</a></p></li> <li id="fn:138"><p>Wiberg 2001, p. 497 <a href="#fnref:138" class="footnote-back-ref">↩</a></p></li> <li id="fn:139"><p>Cerkovnik & Plesničar 2013, p. 7930 <a href="#fnref:139" class="footnote-back-ref">↩</a></p></li> <li id="fn:140"><p>Wiberg 2001, p. 497 <a href="#fnref:140" class="footnote-back-ref">↩</a></p></li> <li id="fn:141"><p>Cross, Saunders & Prinzbach; Chemistry Views 2015 <a href="#fnref:141" class="footnote-back-ref">↩</a></p></li> <li id="fn:142"><p>Sun, Xu & Gao 2013; Anthony 2013 <a href="#fnref:142" class="footnote-back-ref">↩</a></p></li> <li id="fn:143"><p>Nakao 1992 <a href="#fnref:143" class="footnote-back-ref">↩</a></p></li> </ol>