Write the Nernst equation and calculate e.m.f of following cell at 298K.
`Mg(s)|Mg^(2+)(0.130M)||Ag^(+)(0.0001M)|Ag(s)` Given `E_(Mg^(2+)//Mg)^(@)=-2.37V,E_(Ag^(+)//Ag)^(@)=0.80V`. (log 1.3=0.1130)

Explanation

At anode, `Mg rarr Mg^(2+) +2e^(-)`
At cathode,
`ul(2Ag^(+)+2e^(-) rarr Ag)`
`ul(Mg+ 2Ag^(+)rarr Mg^(2+) +Ag)`
`E= E^(@)- (0.059)/(2)"log" ([Mg^(2+)])/([Ag^(+)]^(2))`
`E^(@)= 3.17V`
`E= 3.17 - (0.059)/(2) "log" ((0.130))/((0.0001)^(2))`
`E= 3.17 - (0.059)/(2) (log 12 +6 log 10)`
`E= 3.17 - (0.059)/(2) xx 7.11` = 2.96V