Question

In a compound $C,H$ & $N$ are present in the ratio of $18:2:7$ by weight. The empirical formula of the compound is:

• A. $C_2{H}_6{N}_2$
• B. $C_3{H}_{4}N$
• C. $C_2{H}_8{N}_2$
• D. $C_9{H}_{12}{N}_3$

Answer 1

The correct option is B $C_3{H}_{4}N$

The ratio of weight of $C:H:N=18:2:7$
The ratio of moles of $C:H:N=\frac{18}{12}:\frac{2}{1}:\frac{7}{14}$
$=\frac{3}{2}:2:\frac{1}{2}=3:4:1$
Empirical formula = $C_3{H}_{4}N$