JEE Main 2022 · ChemistryNumerical answerNumerical valueMediumCalculation

JEE Main 30 June 2022, Shift 1, Chemistry Q81

Question 81 of 90 in this shift, Chemistry question 21 of 30, Section B.

Blister copper is produced by reaction of copper oxide with copper sulphide.

2\mathrm{Cu_2O}+\mathrm{Cu_2S}\rightarrow 6\mathrm{Cu}+\mathrm{SO_2}

When

2.86\times10^3

g of

\mathrm{Cu_2O}

and

4.77\times10^3

g of

\mathrm{Cu_2S}

are used for reaction, the mass of copper produced is ___________ g. (nearest integer) (Atomic mass of Cu=63.5 a.m. u S=32.0 a.m. u O=16.0 a.m. u)

Official answer

3810

NTA final key.

Chapter: Some Basic Concepts of Chemistry
Topic: Stoichiometry
Idea tested: Limiting Reagent Identification

Same idea in other shifts

Asked 8× in all

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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.