JEE Main 2019ChemistryChemical EquilibriumMediumMCQ

JEE Main 2019 — Chemical Equilibrium Question with Solution

JEE Main 2019 (12 Jan Shift 1)

Question

In a chemical reaction, A+2B⇌K2C+D , the initial concentration of B was 1.5 times of the concentration of A , but the equilibrium concentrations of A and B were found to be equal. The equilibrium constant K for the chemical reaction is:

Choose an option

Show full solutionCorrect option: B
Correct answer
B4

Step-by-step explanation

A      +      2B      ⇌       2C    +    D
Initial conc. of [A] = a , [B] = 1.5a , [C] = 0 and [D] = 0

At equilibrium [A] = (a - x) , [B] = 1.5(a - 2x) , [C] = 2x and [D] = x

At equilibrium a-x=1.5a-2x

0.5 a=x

a=2x

kC=2x2xa-x1.5a-2x2=4x2.xxx2=4

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About this question

This is a previous-year question from JEE Main 2019, 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.