Question: Who discovered the first five elements in the periodic table and what were the respective years of their discoveries?
Answer: Hydrogen: Henry Cavendish, 1766
Helium: Pierre Janssen, 1868
Lithium: Johan August Arfwedson, 1817
Beryllium: Louis Nicolas Vauquelin, 1798
Boron: Joseph Louis Gay-Lussac, 1808
Categories: Chemistry, History