JEE Main 2021 · ChemistryNumerical answerNumerical valueMediumCalculation

JEE Main 17 March 2021, Shift 1, Chemistry Q56

Question 56 of 90 in this shift, Chemistry question 26 of 30, Section B.

0.01 moles of a weak acid HA (

K_a = 2.0 \times 10^{-6}

) is dissolved in 1.0 L of 0.1 M HCl solution. The degree of dissociation of HA is __________

\times 10^{-5}

(Round off to the Nearest Integer). [Neglect volume change on adding HA. Assume degree of dissociation <<1]

Official answer

NTA final key.

Chapter: Equilibrium
Topic: pH and Buffers
Idea tested: Common Ion Effect on Weak Acid pH

Same topic in other shifts

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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.