JEE Main 2021ChemistrySolutionsMediumNumerical

JEE Main 2021 — Solutions Question with Solution

JEE Main 2021 (27 Jul Shift 2)

Question

In a solvent 50% of an acid HA dimerizes and the rest dissociates. The van't Hoff factor of the acid is _____×10-2 (Round off to the nearest integer)

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Show full solutionCorrect answer: 125
Correct answer
125

Step-by-step explanation

Let initial moles of HA is a

2HA→H2 A20.5a       0.25a

 HA⇌H++  A-0.5a   0.5a   0.5a

Now, i= final moles  initial moles =0.25a+0.5a+0.5a0.5a+0.5a

=1.25=125×10-2

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About this question

This is a previous-year question from JEE Main 2021, covering the Solutions 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.