JEE Main 2025 · ChemistryNumerical answerNumerical valueMediumCalculation

JEE Main 7 April 2025, Shift 2, Chemistry Q72

Question 72 of 75 in this shift, Chemistry question 22 of 25, Section B.

One litre buffer solution was prepared by adding 0.10 mol each of

\mathrm{NH_3}

and

\mathrm{NH_4Cl}

in deionised water. The change in pH on addition of 0.05 mol of HCl to the above solution is __________

\times10^{-2}

. (Nearest integer) Given :

\mathrm{pK_b}

\mathrm{NH_3}=4.745

and

\log_{10}3=0.477

Official answer

NTA final key.

Chapter: Equilibrium
Topic: pH and Buffers
Idea tested: pH Change on Adding Strong Acid/Base to Buffer

Same topic in other shifts

All pH and Buffers questions

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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.