What is the charge on a sulphide ion, S²⁻?

The charge on a sulphide ion is 2− (negative two).

• Sulphur (S) is in Group 16 and has 6 valence electrons.
• To achieve a stable octet, it gains 2 electrons, adding 2− charge: S²⁻.

Examples:

• FeS: Fe²⁺ + S²⁻ → FeS
• Na₂S: 2Na⁺ + S²⁻ → Na₂S

Do not confuse sulphide (S²⁻) with sulphate (SO₄²⁻) or sulphite (SO₃²⁻).

The sulphide ion S²⁻ carries a 2− charge because sulphur gains 2 electrons to complete its octet.