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The standard reductino potentials E^(c-)...

The standard reductino potentials `E^(c-)` for the half reactinos are as follows`:`
`ZnrarrZn^(2+)+2e^(-)" "E^(c-)=+0.76V`
`FerarrFe^(2+)+2e^(-) " "E^(c-)=0.41V`
The `EMF` for the cell reaction
`Fe^(2+)+Znrarr Zn^(2+)+Fe`
is

A

`-0.35V`

B

`+0.35V`

C

`+1.17V`

D

`-1.17V`

Text Solution

Verified by Experts

The correct Answer is:
b
`Fe^(2+)+Znrarr Zn^(2+)+Fe`
`Zn rarr Zn^(2+)+e^(-)," "E^(c-)=+0.76V`
`Fe rarr Fe^(2+)+2e^(-)," "E^(c-)=+0.41V`
These are oxidation potentials.
Reduction potential are equal and opposite.
`Fe` forms cathode and `Zn` forms anode.
`E^(c-)._(cell)=(E^(c-)._(red))_(c)+(E^(c-)._(o x i d))_(a)`
`=(0.41+0.760)V`
`=0.35V`
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