Dithionic acid

<h2 id="synthesis">Synthesis</h2>
<p>Dithionates can be made by <a href="/facts/Redox/Pyd5RVcj">oxidizing</a> a <a href="/facts/Sulfite/xdppUlKA">sulfite</a> (from the +4 to the +5 <a href="/facts/Oxidation_state/W53W6s6V">oxidation state</a>), but on a larger scale they are made by oxidizing a cooled aqueous solution of <a href="/facts/Sulfur_dioxide/jDK1fIDs">sulfur dioxide</a> with <a href="/facts/Manganese_dioxide/HRwgXlUe">manganese dioxide</a>:
</p>
2 MnO2 + 3 SO2  →  MnS2O6 + MnSO4
<p>The manganese dithionate solution formed can then be converted to dithionate salts of other metals by <a href="/facts/Salt_metathesis_reaction/YpadY3lq">metathesis reactions</a>:
</p>
Ba2+ (aq) + MnS2O6 (aq) + MnSO4 (aq)  →  BaSO4 (s)↓ + BaS2O6 · 2 H2O (aq)
<p>Concentrated solutions of dithionic acid can subsequently be obtained treating a barium dithionate solution with sulfuric acid:
</p>
BaS2O6 (aq) + H2SO4 (aq)  →  H2S2O6 (aq) + BaSO4 (s)↓
<h2 id="see-also">See also</h2>
<ul><li><a href="/facts/Sodium_dithionite/wNoKv995">Sodium dithionite</a></li>
<li><a href="/facts/Hypophosphoric_acid/LduLaKG9">Hypophosphoric acid</a>, the phosphorus equivalent.</li></ul>

<h2 id="references">References</h2>

<ol>
<li id="fn:1"><p>Greenwood, Norman  N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN 978-0-08-037941-8. pp. 715-716 <a href="978-0-08-037941-8" target="_blank">978-0-08-037941-8</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li>
</ol>

Dithionic acid open-in-new

Dithionic acid