0.2 g of an organic compound was subjected to estimation of nitrogen by Dumas method in which volume of N 2 evolved (at STP) was found to be 22.400 mL. The percentage of nitrogen in the compound is.[nearest integer] (Given: Molar mass of N 2 is 28 mol -1. Molar volume of N 2 at STP: 22.4 L )

Question

0.2 g of an organic compound was subjected to estimation of nitrogen by Dumas method in which volume of N 2 evolved (at STP) was found to be 22.400 mL. The percentage of nitrogen in the compound is.[nearest integer] (Given: Molar mass of N 2 is 28 mol -1. Molar volume of N 2 at STP: 22.4 L ) (A)  (B)  (C)  (D)

Tardigrade Admin · Accepted Answer

weight of organic compound =0.2 g mass of N 2( g ) evolved =(22.4 × 10-3/22.4) × 28 =28 × 10-3 g % of N =(28 × 10-3/0.2) × 100=14

weight of organic compound =0.2g mass of N2​(g) evolved =22.422.4×10−3​×28 =28×10−3g % of N=0.228×10−3​×100=14

weight of organic compound $= 0.2 g$
mass of $N_{2} (g)$ evolved $= \frac{22.4 \times 1 0 ^{- 3}}{22.4} \times 28$
$= 28 \times 1 0^{- 3} g$
$%$ of $N = \frac{28 \times 1 0 ^{- 3}}{0.2} \times 100 = 14$