Periodic table / Other non-metals

15Phosphorus

Phosphorus is an other non-metal in group 15, period 3. At 25 °C it is a solid.

P
Shells: 2, 8, 5. A simple picture: electrons do not move in circles.
Symbol
P
Atomic number
15 protons in the nucleus
Standard atomic weight
30.974 ± 0.001
Electron configuration
[Ne] 3s2 3p3
Electrons in each shell
2, 8, 5
Group, period, block
15, 3, p
Family
Other non-metals
State at 25 °C
solid
Electronegativity
2.19 (Pauling scale)
First ionisation energy
1011.8 kJ/mol (10.486686 eV)
Where these numbers come from

Atomic weight: IUPAC CIAAW, abridged standard atomic weights 2024. Electron configuration and ionisation energy: NIST Atomic Spectra Database. Family, state and electronegativity: PubChem. See Sources. Melting points, boiling points and densities are left out for now: published values differ between sources, and we will add them once each has been checked.