A button cell used in watches functions as following `Zn(s) + Ag _2 O(s) + H_2 O(l)` `2 A g(s) + Zn^(2+) (aq) = 2 OH^- (aq)` If half cell potentials are `Zn^(2+) (aq) +2e^- rarr Zn (s) , E^@ =- 0. 76 V` `Af_2 O(s) +H_2 O (l) +2e^- rarr` `2Ag(s) + 2OH^- (aq) , E^@ =0. 34 V`. The cell potential will be .A. ` 0.42 V`B. ` 0. 84 V`C. ` 1.10 V`D. ` 1.34 V`

A button cell used in watches functions as following `Zn(s) + Ag _2 O(

1.	A button cell used in watches functions as following `Zn(s) + Ag _2 O(s) + H_2 O(l)` `2 A g(s) + Zn^(2+) (aq) = 2 OH^- (aq)` If half cell potentials are `Zn^(2+) (aq) +2e^- rarr Zn (s) , E^@ =- 0. 76 V` `Af_2 O(s) +H_2 O (l) +2e^- rarr` `2Ag(s) + 2OH^- (aq) , E^@ =0. 34 V`. The cell potential will be .A. ` 0.42 V`B. ` 0. 84 V`C. ` 1.10 V`D. ` 1.34 V`
Answer» Correct Answer - C `E_(cell) = E_(OPZ//Zn^(2) ) + E_(PRAg+//Ag)` `E_(OPZn)^@ + E_(PRAg)^@ + (0.059)/2 log. ([Ag^+]^2)/([Zn^(+2)])` `=0.76 + 0. 34 + (0.095)/5 log.(0)/([Zn^(2+)])` `E_(cell)^@ = 1.10 V`. This is `E_(cell)^@ ` and nor `E_(cell)` since`[ Zn^(2+)]` is not given .

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