Question

Two oxides of an non-metal $X$ contain $50\%$ and $40\%$ of non-metal respectively. If the formula of the first oxide is $X{O}_2$. Then the formula of second oxide is

• A. $X_2{O}_3$
• B. $X_2{O}_5$
• C. $X{O}_3$
• D. $X_{2}O$

Answer 1

Answer: (C)

Given, Formula of first oxide is $X{O}_2$ means one mole of $X=2$ mole of oxygen in the first oxide.

For second Oxide $40\%$ of $(X)$, we have $60\%$ of oxygen.

i.e. For $40\%$ of $(X)$, We have, $2\times 60\%$ of oxygen.

$\therefore$ For $100\%$ of $(X)$ (i.e., one mole) we have, $\frac{2\times 60}{40}=3$ moles of oxygen.

$\therefore$ Formula of second-oxide is $=X{O}_3$.