Question

$2.2$ g of a compound of phosphorous and sulphur has $1.24$ g of $P$ in it. Its empirical formula is :

• A. $P_2{S}_3$
• B. $P_3{S}_2$
• C. $P_3{S}_4$
• D. $P_4{S}_3$

Answer 1

Answer: (D)

$P_4{S}_3$

The ratio of weights of $P:S$ is $1.24:[2.2-1.24]$ = $1.24:0.96$.

The molar ratio is $\frac{1.24}{31}:\frac{0.96}{32}=4:3$.

Therefore, the formula of the compound is $P_4{S}_3$.