`E^(@)` value for `Cu^(2+)//Cu and Fe^(2+)//Fe` are +0.34 V and -0.44 V respectively. Is the reaction `Cu^(2+)+Fe to Cu+Fe^(3+)` spontaneous or not ? Give reason also.

Explanation

Hypothetical reaction is,
Here `Cu^(2+)+Fe to Cu+Fe^(2+)`
Oxidation : `Fe to Fe^(2+)+2e^(-)`
Redution : `Cu^(2+)+2e^(-) to Cu`
Overall : `Cu^(2+)+Fe to Cu+Fe^(2+)`
Cell can be represented as,
`Fe|Fe^(2+)||Cu^(2+)|Cu`
`EMF^(@)=E_((Cu^(2+)//Cu))^(@)-E_((Fe^(2+)//Fe))^(@)`
`=[+0*34-(-0*44)]V`
`=0*78V`
As `EMF^(@)gt0`, the reaction is spontaneous in the given direction.