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Karnataka Board PUCPUC Science 2nd PUC Class 12

Use the data given in below find out the most stable ion in its reduced form.

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Question

Use the data given in below find out the most stable ion in its reduced form.

`"E"_("Cr"_2"O"_7^(2-)//"Cr"^(3+))^⊖`= 1.33 V `"E"_("Cl"_2//"Cl"^-)^⊖` = 1.36 V

`"E"_("MnO"_4^-//"Mn"^(2+))^⊖` = 1.51 V `"E"_("Cr"^(3+)//"Cr")^⊖` = - 0.74 V

Options

  • \[\ce{Cl–}\] 

  • \[\ce{Cr^{3+}}\] 

  • \[\ce{Cr}\]

  • \[\ce{Mn^{2+}}\] 

MCQ
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Solution

\[\ce{Mn^{2+}}\] 

Explanation:

\[\ce{Mn^{2+}}\]  is most stale in its reduced form due to highest E° value.

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Chapter 3: Electrochemistry - Exercises [Page 35]

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NCERT Exemplar Chemistry Exemplar [English] Class 12
Chapter 3 Electrochemistry
Exercises | Q I. 11. | Page 35

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