Question

0.2 g of an organic compound was subjected to estimation of nitrogen by Duma’s method in which volume of N2 evolved (at STP) was found to be 22.400 mL. The percentage of nitrogen in the compound is _____. [nearest integer]
(Given : Molar mass of N2 is 28 g mol–1, Molar volume of N2 at STP : 22.4L)

Answer 1

The correct answer is 14
Mass of organic compound = 0.2 g
Volume of $N_2$ gas evolved at STP = 22.4 mL
Mass of $N_2$ gas evolved
$= \frac{22.4 × 10^{−3} × 28}{22.4}$
= 0.028 g
Percentage of nitrogen in the compound :
$=\frac{0.028×100}{0.2}$
=14%