Question

The relative number of atoms of elements, $X$ and $Y$ in a compound is 0.25 and 0.5. The empirical formula of compound is:

• A. $XY$
• B. $X_{2}Y$
• C. $X{Y}_2$
• D. $X_2{Y}_2$

Answer 1

The correct option is C $X{Y}_2$

Let the empirical formula be $X_a{Y}_b$

Atoms of $X=0.25$

Atoms of $Y=0.5$

% of $X=$ $0.25/(0.25+0.5)\times 100=33$%

% of $Y=$ $0.5/(0.25+0.5)\times 100=67$%

The simplest ratio of the two is $X{Y}_2$.

Hence, option $C$ is correct.