Question:
The ammonia $\left(\mathrm{NH}_{3}\right)$ released on quantitative reaction of $0.6 \mathrm{~g}$ urea $\left(\mathrm{NH}_{2} \mathrm{CONH}_{2}\right)$ with sodium hydroxide $(\mathrm{NaOH})$ can be neutralized by:
Correct Option: , 3
Solution:
$1 \mathrm{~mol}$ of urea $=2 \mathrm{~mol}$ of $\mathrm{NH}_{3}$
$60 \mathrm{~g}$ of urea $=2 \mathrm{~mol}$ of $\mathrm{NH}_{3}$
$0.6 \mathrm{~g}$ of urea $=\frac{2}{60} \times 0.6 \mathrm{~mol}=0.02 \mathrm{~mol}$ of $\mathrm{NH}_{3}$
$\mathrm{mol}$ of $\mathrm{NH}_{3}=\mathrm{mol}$ of $\mathrm{HCl}$
$\therefore \mathrm{mol}$ of $\mathrm{HCl}=0.02 \mathrm{~mol}$
$\Rightarrow$ Normality of $\mathrm{HCl}=0.2 \mathrm{~N}$
Volume of $\mathrm{HCl}=100 \mathrm{~mL}$