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 $N{H}_3$ per cc 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

The correct option is A $0.17$ $g/c{m}^3$

Density $=\frac{mass}{volume}$

Mass $=$ density $\times$ volume

Density $=$ 0.93g/cc

Mass of 1 cc of solution $=0.93\times 1=0.93g$

The solution contains 18.6% ammonia by weight.

So, 1 cc of solution $=18.6\%$ of 0.93g ammonia

$=\frac{18.6\times 0.93}{100}=$ 0.173 g/cm${}^3$

Hence, the correct option is $A$