Write Nernst equation and calculate e.m.f. of the cell at 298 k.
`Mg(s)|Mg^(2+)(0.001 M)||Cu^(2+)(0.0001M)|Cu(s)`

Explanation

Cell representation is,
`Mg(s)|Mg^(2+)(10^(-3)M)||Cu^(2+)(10^(-4)M)|Cu(s)`
cell reaction are
Oxidation : `Mg(s) to Mg^(2+)(aq)+2e^(-)`
Reduction : `Cu^(2+)(aq)+2e^(-) to Cu(s)`
Overall : `Mg(s)+Cu^(2+)(aq)toMg^(2+)(aq)+Cu(s)`
Here n=2