Interactive Periodic Table
Click on an element to see its detailed properties. Use the filters to highlight different categories, blocks, or phases.
1
H
Hydrogen
diatomic nonmetal
Hydrogen is a chemical element with chemical symbol H and atomic number 1. With an atomic weight of 1.00794 u, hydrogen is the lightest element on the periodic table. Its monatomic form (H) is the most abundant chemical substance in the Universe, constituting roughly 75% of all baryonic mass.
| Atomic Mass | 1.0080 u |
| Electronegativity | 2.2 |
| Ionization Energy (1st) | 1312 kJ/mol |
| Melting Point | 13.99 K |
| Boiling Point | 20.27 K |
| Density | 0.08988 g/cm³ |
| Discovered By | Henry Cavendish |
Temperature
°C °F K
Gas
Liquid
Solid