JEE Main 2020 · ChemistryNumerical answerNumerical valueMediumCalculation

JEE Main 2 September 2020, Shift 2, Chemistry Q48

Question 48 of 75 in this shift, Chemistry question 23 of 25.

For the disproportionation reaction

2\,\mathrm{Cu^+(aq)} \rightleftharpoons \mathrm{Cu(s)} + \mathrm{Cu^{2+}(aq)}

at 298 K,

\ln K

(where K is the equilibrium constant) is __________

\times10^{-1}

. Given : (

E^0_{\mathrm{Cu^{2+}/Cu^+}} = 0.16

E^0_{\mathrm{Cu^+/Cu}} = 0.52

\frac{RT}{F} = 0.025

)

Official answer

144.00

NTA final key (Sep 2020).

Chapter: Electrochemistry
Topic: Nernst Equation
Idea tested: Equilibrium Constant of Disproportionation

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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 108 of the 174 JEE Main shifts held from 2017 to 2026.