Question

Ammonia gas is passed into water, yielding a solution of density $0.93$ $g/c{m}^3$ and containing $18.6\%$ $N{H}_3$ by weight. The mass of $N{H}_{3}percc$ of the solution is:

• A. $0.17$ $g/c{m}^3$
• B. $0.34$ $g/c{m}^3$
• C. $0.51$ $g/c{m}^3$
• D. $0.68$ $g/c{m}^3$

Answer 1

Answer: (A)

$0.17$ $g/c{m}^3$

Volume of solution $={\text{1 cm}}^3$

Density of solution $={\text{0.93 g/cm}}^3$

$\text{Density}=\frac{\text{Mass}}{\text{volume}}$

$\text{Mass}=\text{Density}\times \text{volume}$

$\text{Mass}={\text{0.93 g/cm}}^3\times {\text{1 cm}}^3=\text{0.93 g}$

Weight percent of $N{H}_3=\text{18.6}\%$

The mass of $N{H}_3$ per cc of solution

$=\text{0.93 g}\times \frac{18.6}{100}={\text{0.17 g/cm}}^3$

Hence, the correct option is $A$