Zinc/silver oxide cell is used in hearing aids and electric watches. The following reactions occur : `Zn(s) to Zn^(2+)(aq)+2e^(-) , E_(Zn^(2+)//Zn)^(@)=-0.76V` `Ag_(2)O+H_(2)O+2e^(-) to2Ag+2OH^(-),E_(Ag^(+)//Ag)^(@)=0.344" V"` Calculate (i) Standard potential of the cell (ii) Standard Gibbs energy.

Zinc/silver oxide cell is used in hearing aids and electric watches. T

1.	Zinc/silver oxide cell is used in hearing aids and electric watches. The following reactions occur : `Zn(s) to Zn^(2+)(aq)+2e^(-) , E_(Zn^(2+)//Zn)^(@)=-0.76V` `Ag_(2)O+H_(2)O+2e^(-) to2Ag+2OH^(-),E_(Ag^(+)//Ag)^(@)=0.344" V"` Calculate (i) Standard potential of the cell (ii) Standard Gibbs energy.
Answer» In this reaction, Zn is oxidised and `Ag_(2)O` is reduced (i)`" "E_(cell)^(@)=E_(cathode)^(@)-E_(anode)^(@)` `=(0.344)-(-0.76)=1.104" V"` (ii) `" " DeltaG^(@)=-nFE_(cell)^(@)` `=-2xx(96500" C mol"^(-1))xx(1.104" V")` `=-2.13xx10^(5)" CV "mol^(-1)` `=-2.13xx10^(5)" J mol"^(-1)`

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Zinc/silver oxide cell is used in hearing aids and electric watches. The following reactions occur : `Zn(s) to Zn^(2+)(aq)+2e^(-) , E_(Zn^(2+)//Zn)^(@)=-0.76V` `Ag_(2)O+H_(2)O+2e^(-) to2Ag+2OH^(-),E_(Ag^(+)//Ag)^(@)=0.344" V"` Calculate (i) Standard potential of the cell (ii) Standard Gibbs energy.

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