JEE Main 2025 · ChemistryNumerical answerNumerical valueEasyCalculation

JEE Main 7 April 2025, Shift 1, Chemistry Q74

Question 74 of 75 in this shift, Chemistry question 24 of 25, Section B.

An organic compound weighing 500 mg, produced 220 mg of

\mathrm{CO_2}

, on complete combustion. The percentage composition of carbon in the compound is ________%. (nearest integer) (Given molar mass in

\mathrm{g\,mol^{-1}}

of C:12, O:16)

Official answer

NTA final key.

Chapter: Organic Chemistry: Some Basic Principles and Techniques
Topic: Stoichiometry
Idea tested: POAC in Combustion Analysis

Same idea in other shifts

Asked 3× in all

2 Apr 2026, Shift 2 · Q62Complete combustion of X g of an organic compound gave 0.25 g of $CO_2$ and 0.12 g of $H_2O$ . If the % of carbon is 25% and of hydrogen is…MediumSingle correct
28 Jun 2022, Shift 2 · Q88The complete combustion of 0.492 g of an organic compound containing ‘C’, ‘H’ and ‘O’ gives 0.793g of $\mathrm{CO_2}$ and 0.442 g of…MediumNumerical value

Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.