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MnO4^(-) + 8H^(=) + 5e^(-) rarr Mn^(2+) ...

`MnO_4^(-) + 8H^(=) + 5e^(-) rarr Mn^(2+) + 4 H_2 O`
If `H^(+)` concentration is decreaded from 1M to `10^(-4) M` at `25^@ C`.

A

the otential decreases by ` 0. 38 V` with decrease in oxidising power

B

the potential increases by ` 0. 30 V` with increase in oxidising power

C

the potential dereases by ` 0 .25 V` with decreases in oxidising power

D

the potential dercreases by ` 0. 38 V` without affecting oxidising power

Text Solution

Verified by Experts

The correct Answer is:
A
` Delta E = (0.0591 xx log)/5 [10^(-4)]^8 =- 0.378 V`.
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A2Z-ELECTROCHEMISTRY-Construction And Working Of A Cell, Electrochemical Series And Its Applications
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