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Karnataka Board PUCPUC Science 2nd PUC Class 12

Consider the reaction: Cr2⁢O⁢2−7 + 14⁢H⁡++6e− -> 2Cr3+ + 7⁢H⁡2⁢O What is the quantity of electricity in coulombs needed to reduce 1 mol of Cr2⁢O⁢2−7?

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Question

Consider the reaction:

\[\ce{Cr2O^{2-}_7 + 14H+ + 6e- -> 2Cr^{3+} + 7H2O}\]

What is the quantity of electricity in coulombs needed to reduce 1 mol of  \[\ce{Cr2O^{2-}_7}\]?

Numerical
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Solution

According to the given reaction,

\[\ce{Cr2O^{2-}_7}\] One mole of ions requires 6 moles of electrons.

∴ F = 6 × 96500 C

= 579000 C

∴ The 579000 C of electricity is required to reduce 1 mol of \[\ce{Cr2O^{2-}_7}\].

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Chapter 2: Electrochemistry - Intext Questions [Page 54]

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NCERT Chemistry Part 1 and 2 [English] Class 12
Chapter 2 Electrochemistry
Intext Questions | Q 2.12 | Page 54

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