Hydrogen is the first element in the periodic table. It has an atomic number of 1, and an atomic mass of 1.00784 u.
History of Hydrogen:
Hydrogen is the most simple and abundant element in the universe. In 1766, a scientist named Henry Cavendish discovered it and termed it “inflammable air”. In 1783, Antoine Lavoisier named it “hydrogen”, meaning “water former”.
Hydrogen is now used for green energy, storage, and industrial applications.
More Info
| Atomic number | 1 |
| Atomic mass | 1.00784 u |
| Melting point | -434.5°F |
| Boiling point | -423.2°F |
| Density |  (roughly 14 times lower than air) |