- Atomic Radius (Å)
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.
1
Atomic Number
1.01
Atomic Mass (u)
14.18
Melting Point (K)
20.28
Boiling Point (K)
0.09
Density (solid: g/cm³, gas: g/liter)
0.79
Atomic Radius (Å)
0.31
Covalent Radius (Å)
2.2
Electronegativity
13.6
First Ionization Energy (eV)
72.77
Electron Affinity
1
Number of Shells
1
Electron Valency
1
Electron Shell Occupations
14.3
Specific Heat (J/g)