Question

What is the percentage composition of the elements in ammonia ($N{H}_3$)?

$(N=14,H=1)$

• A. $N=82.35$ %, $H=17.65$ %
• B. $N=81.35$ %, $H=18.65$ %
• C. $N=80.35$ %, $H=19.65$ %
• D. $N=42.35$ %, $H=57.65$ %

Answer 1

Answer: (A)

$N=82.35$ %, $H=17.65$ %

Molecular weight of ${NH}_3=17g$

$17g$ of ${NH}_3$ contains $14g$ of $N$ and $3g$ of $H$

$\therefore$ % of $H=\frac{3}{17}\times 100=17.65$%

$\therefore$ % of $N=\frac{14}{17}\times 100=82.35$%