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Science
Chemistry
Chemical elements
s-Block
Group 1
Group 1
Alkali metal
Group of highly-reactive chemical elements
Caesium
Chemical element with atomic number 55
Francium
Chemical element with atomic number 87
Isotopes of lithium
Lithium
Chemical element with atomic number 3 (Li)
Potassium
Chemical element with atomic number 19 (K)
Potassium-40
Radioactive isotope of potassium
Rubidium
Chemical element with atomic number 37
Sodium
Chemical element with atomic number 11