Question

Write the formula and names of the compounds formed between :
Sodium and sulphide ions

Answer 1

Sodium and Sulphide ions:

1. Sodium ions are cations and are denoted as ${\mathrm{Na}}^{+}$.
2. Sulphide ions are anions and are denoted as ${\mathrm{S}}^{2-}$.

Compound:

1. Sodium ions combine with Sulphide ions to form the compound Sodium sulphide.
2. The valencies interchange, the valency of suphide ion is 2 which moves to sodium ion and the valency of sodium ion is 1 which moves to sulphide ion.
3. Hence, Sodium sulphide has the chemical formula ${\mathrm{Na}}_2\mathrm{S}$.