Question

Write down the formulae of the following compounds:

(i) Potassium oxide

(ii) Aluminium Nitride

(iii) Hydrogen sulfide

(iv) Calcium hydroxide

Answer 1

(i) Valency of potassium is 1 and valency of oxygen is 2 hence chemical formula will be $K_{2}O$.

(ii) Valency of Aluminium is 3 and valency of Nitrogen is also 3, hence the chemical formula is AlN.

(iii) Valency of Hydrogen is 1 and valency of Sulphur is 2, hence the chemical formula is $H_{2}S$.

(iv) Valency of Calcium is 2 and valency of Hydroxide ion is 1, hence the chemical formula is $Ca{\left(OH\right)}_2.$