Question

If the valency of hydrogen is 1 and that of nitrogen is 3, work out the formula for ammonia.

Answer 1

Valency of hydrogen = 1
Valency of nitrogen = 3
Ammonia consists of nitrogen and hydrogen.

$\begin{array}{ccc}\mathrm{Elements}:& \mathrm{N}& \mathrm{H}\\ \mathrm{Valencies}:& 3& 1\end{array}$

Formula for ammonia can be worked out by crossing the valencies of the constituent elements.

Therefore, formula of ammonia is NH₃.