JEE Main 2021ChemistryChemical EquilibriumHardNumerical

JEE Main 2021 — Chemical Equilibrium Question with Solution

JEE Main 2021 (27 Aug Shift 1)

Question

The number of moles of NH3, that must be added to 2 L of 0.80MAgNO3 in order to reduce the concentration of Ag+ ions to 5.0×10-8MKformation  for AgNH32+=1.0×108 is __________. (Nearest integer)
[Assume no volume change on adding NH3]

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Show full solutionCorrect answer: 4
Correct answer
4

Step-by-step explanation

Let no. moles of NH3 added =x

Ag+(aq)+2NH3(aq)⇌AgNH32+(aq)

t=0 0.8 x2

t=∞ 5×10-8 x2-1.6 0.8

Keq=AgNH32+Ag+NH32

x2-1.6=0.4

x=4

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About this question

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