Chemistry · Some Basic Concepts of Chemistry (Mole Concept) + Stoichiometry

JEE Main 2026 — 2 April, Evening Shift — Question 48

The ratio of mass percentage (w/w)(\mathrm{w} / \mathrm{w}) of C:H\mathrm{C}: \mathrm{H} in a hydrocarbon is 12:112: 1. It has two carbon atoms. The weight (in g ) of CO2( g)\mathrm{CO}_{2}(\mathrm{~g}) formed when 3.38 g of this hydrocarbon is completely burnt in oxygen is :(Given : Molar mass in gmol−1C:12,H:1,O:16\mathrm{g} \mathrm{mol}^{-1} \mathrm{C}: 12, \mathrm{H}: 1, \mathrm{O}: 16 )

  1. Option A:

    5.68

  2. Option B:

    11.44

    Correct
  3. Option C:

    22.74

  4. Option D:

    17.05

Answer: B

Step-by-step solution

Molecular formula of hydrocarbon is C2H2\mathrm{C}_{2} \mathrm{H}_{2} Moles of C2H2=3.3826\mathrm{C}_{2} \mathrm{H}_{2}=\frac{3.38}{26} C2H2( g)+52O2( g)→2CO2( g)+H2O(l)\mathrm{C}_{2} \mathrm{H}_{2}(\mathrm{~g})+\frac{5}{2} \mathrm{O}_{2}(\mathrm{~g}) \rightarrow 2 \mathrm{CO}_{2}(\mathrm{~g})+\mathrm{H}_{2} \mathrm{O}(l) Moles of CO2\mathrm{CO}_{2} produced =(3.3826×2)=\left(\frac{3.38}{26} \times 2\right) Mass of CO2\mathrm{CO}_{2} produced =(3.3826×2)×44=11.44=\left(\frac{3.38}{26} \times 2\right) \times 44=11.44

Answer key and solution verified before publishing.

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Exam
JEE Main 2026
Subject
Chemistry
Chapter
Some Basic Concepts of Chemistry (Mole Concept) + Stoichiometry
Topic
Percentage composition & Empirical Formula
The ratio of mass percentage ( w / w ) of C : H in a hydrocarbon is… | JEE Main 2026 PYQ with Solution · DhiX AI