JEE Main 2014 — Electrochemistry Question with Solution
From: JEE Main 2014 (Offline)
Question
Given below are the half-cell reactions:
Mn2+ + 2e- Mn; Eo = -1.18 V
2(Mn3+ + e- Mn2+); Eo = +1.51 V
The Eo for 3Mn2+ Mn + 2Mn3+ will be :
Mn2+ + 2e- Mn; Eo = -1.18 V
2(Mn3+ + e- Mn2+); Eo = +1.51 V
The Eo for 3Mn2+ Mn + 2Mn3+ will be :
Choose an option
Show full solutionCorrect option: C
Correct answer
C– 2.69 V; the reaction will not occur
Step-by-step explanation
(a)
(b)
Now multiplying equation by two and subtracting from equation
[ value of (i.e., ) shows that the reaction is non-spontaneous ]
(b)
Now multiplying equation by two and subtracting from equation
[ value of (i.e., ) shows that the reaction is non-spontaneous ]
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This is a previous-year question from JEE Main 2014, 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.