If `E_(Fe^(2+))^(@)//Fe = -0.441 V`
and `E_(Fe^(3+))^(@)//Fe^(2+) = 0.771 V`
The standard `EMF` of the reaction
`Fe+2Fe^(3+) rarr 3Fe^(2+)`
will be:

Options

A. 0.330 V
B. 1.653 V
C. 1.212 V
D. 0.111 V

Answer

C

Explanation

For the cell reaction
`Fe+2Fe^(3+)to3Fe^(2+)`
Anode reaction is `Fe to Fe^(2+)+2e^(-)`
Cathode reaction is `2Fe^(3+)+2e to 2Fe^(2+)`
`E_(cell)^(@)=E_(Cathode)^(@)-E_(Anode)^(@)(E^(@)"is reduction potential")`ltbrge0.771-(-0.441)
`E_(Cell)^(@)=1.212 V`