JEE Main 2021ChemistryElectrochemistryHardNumerical

JEE Main 2021 — Electrochemistry Question with Solution

JEE Main 2021 (27 Jul Shift 1)

Question

The conductivity of a weak acid HA of concentration 0.001 mol L-1 is 2.0×10-5 S cm-1. If Λm0(HA)=190 S cm2 mol-1, the ionization constant Ka of HA is equal to ____ ×10-6
(Round off to the Nearest Integer)

Enter your answer

Show full solutionCorrect answer: 12
Correct answer
12

Step-by-step explanation

Λm=1000×KM
=1000×2×10-50.001=20 S cm2 mol-1

⇒α=ΛmΛm∞=20190=219

=12.3×10-6

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About this question

This is a previous-year question from JEE Main 2021, covering the Electrochemistry chapter of Chemistry. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.