JEE Main 2021 · ChemistryNumerical answerNumerical valueHardMulti-step

JEE Main 3 August 2021, Shift 1, Chemistry Q55

Question 55 of 90 in this shift, Chemistry question 25 of 30, Section B.

If 1 M solution of acetic acid is diluted

x

times so that pH of the solution is doubled. The value of of

x

is (

\mathrm{K_a}

= 1.8×

10^{-5}

) ________. (Nearest integer)

Official answer

55555

NTA final key.

Chapter: Equilibrium
Topic: pH and Buffers
Idea tested: pH of Weak Acids and Bases

Same idea in other shifts

Asked 4× 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.