1 H 1.008
Hydrogen
diatomic nonmetal
Properties
- Atomic number
- 1
- Atomic mass
- 1.008 u
- Category
- diatomic nonmetal
- Group
- 1
- Period
- 1
- Block
- s-block
- State (room temp)
- Gas
- Outer-shell electrons
- 1
- Electronegativity
- 2.2 (Pauling)
- Density
- —
- Melting point
- -259.16 °C
- Boiling point
- -252.88 °C
Electron configuration
1s¹
Noble-gas shorthand: 1s¹
Electrons per shell: 1 — that's 1 in the outermost shell.
About Hydrogen
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.
- Discovered by Henry Cavendish
- Named by Antoine Lavoisier
- Appearance: colorless gas
Position in the periodic table
Data compiled from Wikipedia, PubChem, and IUPAC. Source.