1 - Hydrogen diatomic nonmetal
Discovered by Henry Cavendish in 1766
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.
H He Li Be B C N O F Ne Na Mg Al Si P S Cl Ar K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe Cs Ba La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn Fr Ra Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr Rf Db Sg Bh Hs Mt Ds Rg Cn Nh Fl Mc Lv Ts Og
57-71 La-Lu Lanthanides
89-103 Ac-Lr Actinides
| Shell | Electrons | Orbitals |
|---|---|---|
| 1 | 1 | 1 in 1s |
1.01 u Atomic Mass
0.79 Å Atomic Radius
20.3 K Boiling Point
0.31 Å Covalent Radius
0.0000899 g/cm³ Density
72.8 Electron Affinity
2.2 Electronegativity
13.6 eV First Ionization Energy
14.2 K Melting Point
1 Number of Shells
1 Electron Valency
1 Atomic Number
1 Electron Shell Occupations
14.3 J/(g K) Specific Heat