Phosphorus

Atomic number15
Atomic weight30.973762
Discovery (year)1669
Atomic radius (A)1.09
Melting point (oC)44.1
Boiling point (oC)279.8
Density (g/cm3)1.83
Specific heat (cal/g oC)0.177
Ionization potential (eV)10.486
Electron Affinity (eV)0.7464