Phosphorus

Chaitra 26/06/2026 19:58:08 Updated 26/06/2026 19:58:08

Property	Value
Atomic Number	15
Element	Phosphorus
Symbol	P
Atomic Mass	30.974 u
Number of Neutrons	16 (most common isotope, Phosphorus-31)
Number of Protons	15
Number of Electrons	15
Period	3
Group	15
Phase	Solid
Radioactive	No
Natural	Yes
Metal	No
Nonmetal	Yes
Metalloid	No
Type	Polyatomic Nonmetal
Atomic Radius	98 pm
Electronegativity	2.19 (Pauling scale)
First Ionization Energy	10.487 eV
Density	1.82 g/cm³ (white phosphorus)
Melting Point	44.15 °C
Boiling Point	280.5 °C
Number of Isotopes	1 stable (Phosphorus-31)
Discoverer	Hennig Brand
Year	1669
Specific Heat	0.769 J/g·K
Number of Shells	3
Number of Valence Electrons	5