JEE Main 2019ChemistryElectrochemistryHardMCQ

JEE Main 2019 — Electrochemistry Question with Solution

JEE Main 2019 (09 Jan Shift 2)

Question

If the standard electrode potential for a cell is 2 V at 300 K, the equilibrium constant K for the reaction.

Zns+Cu2+aq⇌Zn2+aq+Cus 

at 300 K is approximately:

R=8 JK-1mol-1, F=96000 C mol-1

Choose an option

Show full solutionCorrect option: C
Correct answer
Ce160

Step-by-step explanation

∆G=∆Go+RTlnQ
At equilibrium ∆G=0, Q=k
0=∆Go+RT lnK
∆Go=-RT lnK ∴∆Go=-nFEo
So -nFEo=-RT lnk
′n′ factor for the above cell =2
So -2×96000×2=-8×300 lnk
lnk=160
k=e160

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About this question

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