Question

A metal nitride, $M_3{N}_2$ contains $28\%$ of nitrogen. The atomic mass of metal, $M$ is ____

Answer 1

Answer: 24

In the given metal nitride, nitrogen present is $28\%$ that means, the nitride contains $28g$ nitrogen and $72g$ metal.

Moles of metal $=\frac{72}{x}$

Moles of nitrogen $=\frac{28}{14}=2$

$\Rightarrow$ Molar ratio, $M:N=\frac{72}{x}:2=3:2$

$\frac{72}{x}=3$

$\therefore x=24$