Question

10 ml of a compound containing 'N' and 'O' is mixed with 30 ml of $H_2$ to produce $H_{2}O$ (l) and 10 ml of $N_2$(g). Molecular formula of compound if both reactants reacts completely, is:

• A. $N_{2}O$
• B. $N{O}_2$
• C. $N_2{O}_3$
• D. $N_2{O}_5$

Answer 1

Answer: (C)

$N_2{O}_3$

At STP 1 mole of any gas occupies 22.4 L. Hence, the volume of the gases can be correlated to the number of moles of gases. 10 ml of compound reacts with 30 ml of hydrogen to produce water and 10 ml of nitrogen. Thus, for every one mole of the compound, 3 moles of hydrogen reacts to produce water and 1 mole of nitrogen.
$X+3H_2\to H_{2}O+N_2$
This equation will be balanced when the formula of the compound is ,

$N_2{O}_3$, $N_2{O}_3+3H_2\to 3H_{2}O+N_2$