JEE Main 2026 · ChemistryMultiple choiceSingle correctMediumCalculation

JEE Main 2 April 2026, Shift 2, Chemistry Q56

Question 56 of 75 in this shift, Chemistry question 6 of 25, Section A.

At 25°C, 20.0 mL of 0.2 M weak monoprotic acid HX is titrated against 0.2 M NaOH. The pH of the solution (a) at the start of the titration (when NaOH has not been added) and (b) when 10 mL of NaOH is added respectively, are: Given:

K_a = 5 \times 10^{-4}

pKa = 3.3

\alpha < < 1

(a) _____ (b) _____

(1)0.7 2.0
(2)2.0 3.3Official answer
(3)1.1 2.2
(4)3.0 2.2

Official answer

Option 2

NTA final key.

Chapter: Equilibrium
Topic: pH and Buffers
Idea tested: pH at Titration Half-Equivalence Point

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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 42 of the 174 JEE Main shifts held from 2017 to 2026.