Chemistry · Practical Organic Chemistry

JEE Main 2025 — 7 April, Evening Shift — Question 21

In Dumas' method 292 mg of an organic compound released 50 mL of nitrogen gas (N2)\left(\mathrm{N}_{2}\right) at 300 K temperature and 715 mm Hg pressure. The percentage composition of ' N ' in the organic compound is _____\_\_\_\_\_ % (Nearest integer) (Aqueous tension at 300 K=15 mmHg300 \mathrm{~K}=15 \mathrm{~mm} \mathrm{Hg} )

Answer: 18

Numerical answer — enter this value.

Step-by-step solution

VN2V_{N_{2}} at STP =273×(715−15)×50300×760=\frac{273 \times(715-15) \times 50}{300 \times 760}

=41.9 mL=41.9 \mathrm{~mL}

MN2=41.922400×28=0.052 gM_{N_{2}}=\frac{41.9}{22400} \times 28=0.052 \mathrm{~g}

% N=0.052 g0.292×100=17.94%\% \mathrm{~N}=\frac{0.052 \mathrm{~g}}{0.292} \times 100=17.94 \%

Answer key and solution verified before publishing.

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Exam
JEE Main 2025
Subject
Chemistry
Chapter
Practical Organic Chemistry
Topic
Quantitative organic analysis
In Dumas' method 292 mg of an organic compound released 50 mL of… | JEE Main 2025 PYQ with Solution · DhiX AI