Question

A button cell used in watches functions as follows:
`Zn(s)+Ag_(2)O(s)+H_(2)O(l)hArr2Ag(s)+Zn^(2+)(aq)+2OH^(-)(aq)`
The half-cell potential are
`Zn^(2+)(aq)+2e^(-)toZn(s),E^(@)=-0.76V`
`Ag_(2)O(s)+H_(2)O(l)+2e^(-)to2Ag(s)+2OH^(-)(aq),E^(@)=0.34V`
The cell potential will be
A. 1.10 V
B. 0.42 V
C. 0.84 V
D. 1.34V

Answer 1

Correct Answer - A
`E_(cell)^(@)=E_("cathode")^(@)-E_("anode")^(@)=0.34-(-0.76)V=1.10V`