Question

`Delta_rG^@` for the cell with the cell reaction : `Zn_((s))+ Ag_2O_((s)) + H_2O_((l)) to Zn_((aq))^(2+) + 2Ag_((s)) + 2OH_((aq))^(-)`
`[E_(Ag_2O // Ag)^(@)=0.344 V, E_(Zn^(2+)//Zn)^@=-0.76 V]`
A. `2.13xx10^5 "J mol"^(-1)`
B. `-2.13xx10^5 "J mol"^(-1)`
C. `1.06xx10^5 "J mol"^(-1)`
D. `-1.06xx10^5 "J mol"^(-1)`

Answer 1

Correct Answer - B
`E_"cell"^@=E_(Ag_2O //Ag)^@-E_(Ag^(2+)//Zn)^@`
=0.344-(-0.76)=1.104 V
`DeltaG^@= -FE_"cell"^@= - 2 xx 96500 xx 1.104 = - 2.13 xx 10^5 " J mol"^(-1)`