For the reaction, $\mathrm{6I^-_{(aq)} + Cr_2O_7^{2-}{}_{(aq)} + 14H^+ \longrightarrow 3I_{2(aq)} + 2Cr^{3+}{}_{(aq)} + 7H_2O_{(aq)}}$ ; $\mathrm{E^0_{cell} = 0.79V}$ The standard reduction potential for $\mathrm{I_{2(aq)}}$ is $x \times10^{-2}$ V. The value of $x$ is ________. (Nearest integer) [Given : The standard reduction potential for ($\mathrm{Cr_2O_7^{2-}{}_{(aq)} \rightarrow 2Cr^{3+}}$ is 1.33 V]

JEE Main 2021 · ChemistryNumerical answerNumerical valueEasyCalculation

JEE Main 4 August 2021, Shift 1, Chemistry Q56

Question 56 of 90 in this shift, Chemistry question 26 of 30, Section B.

For the reaction,

\mathrm{6I^-_{(aq)} + Cr_2O_7^{2-}{}_{(aq)} + 14H^+ \longrightarrow 3I_{2(aq)} + 2Cr^{3+}{}_{(aq)} + 7H_2O_{(aq)}}

;

\mathrm{E^0_{cell} = 0.79V}

The standard reduction potential for

\mathrm{I_{2(aq)}}

x \times10^{-2}

V. The value of

x

is ________. (Nearest integer) [Given : The standard reduction potential for (

\mathrm{Cr_2O_7^{2-}{}_{(aq)} \rightarrow 2Cr^{3+}}

is 1.33 V]

Official answer

NTA final key.

Chapter: Electrochemistry
Topic: Nernst Equation
Idea tested: Standard Cell Potential

Same idea in other shifts

Asked 13× in all

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11 Apr 2023, Shift 2 · Q86The number of correct statements from the following is _______ A. $\mathrm{E_{cell}}$ is an intensive parameter B. A negative…MediumNumerical value
28 Jul 2022, Shift 1 · Q70Which of the following has least tendency to liberate $\mathrm{H_2}$ from mineral acids ?EasySingle correct

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.