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 Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn
Fr Ra Ac Rf Db Sg Bh Hs Mt Ds Rg Cn Nh Fl Mc Lv Ts Og
Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu
Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr
Electron Configuration: [Ar]4s1
Electronegativity: 0.82
Atomic Radius: 275 pm
Ionization Energy: 4.341 eV
Electron Affinity: 0.501 eV
Oxidation States: 1
Standard State: Solid
Melting Point: 336.53 K
Boiling Point: 1032 K
Density: 0.89 g/cm3
Family: Alkali metal
Year Discovered: 1807
Number of Neutrons: 20
Number of Protons: 19
Number of Electrons: 19
Number of Valence: 1
Valency: 1
Group: 1
Period: 4
Shell: s-shell
Specific Heat: 0.757 J/g K
Radioactive: 0
Occurrence: Natural
Source: Dying high-mass stars