JEE Main 2020 · ChemistryNumerical answerNumerical valueHardMulti-step

JEE Main 2 September 2020, Shift 2, Chemistry Q50

Question 50 of 75 in this shift, Chemistry question 25 of 25.

The ratio of the mass percentages of ‘C & H’ and ‘C & O’ of a saturated acyclic organic compound ‘X’ are 4 : 1 and 3 : 4 respectively. Then, the moles of oxygen gas required for complete combustion of two moles of organic compound ‘X’ is __________.

Official answer

5.00

NTA final key (Sep 2020).

Chapter: Some Basic Concepts of Chemistry
Topic: Mole Concept
Idea tested: Empirical Formula from Mass Percentage

Same idea in other shifts

Asked 6× in all

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28 Jun 2022, Shift 2 · Q61Compound A contains 8.7% Hydrogen, 74% Carbon and 17.3% Nitrogen. The molecular formula of the compound is, Given : Atomic masses of C, H…MediumSingle correct

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.