A strip of nickel metal is placed in a 1molar solution of `Ni(NO_3)_2` and a strip of silver metal is placed in a one molar solution of `AgNO_3`. An electrochemical cell is created when the two solution are connected by a salt bridge and the two strips are connected by wires to a voltmeter.
(a) Write the balanced equation for the overall reaction occuring in the cell and calculate the cell potential.
(b) Calculate the cell potential, E at `25^@C` for the cell, if the initial concentration of `Ni(NO_3)_2` is 0.100 molar and the initial concentration of `AgNO_3` is 1.00 molar.
`[E_(Ni^(2+)//Ni)^@=-0.25V, E_(Ag^+//Ag)^@=0.80 VJ]`
`log10^-1=-1`

Explanation

(i) `Ni(s)to Ni^(2+) (aq) +2e^-`
`2Ag^+ (aq)+2e^(- ) to 2Ag (s) `
`Ni(s)+2Ag^+ (aq)to Ni^(2+) (aq)+2Ag(s)`
`E_(cell)^@=E_(cathode)^@-E_(anode)^@`
`=0.80-(-0.25)=1.05 V`
(ii) `E_(cell)=E_(cell)^@-0.0591/2log""([Ni^(2+)])/([Ag^+]^2)`
`=E_(cell)^@-0.0591/2log""0.1/(1)^2`
`=0.05 -0.0591/2 times (-1)`
`=1.05 +0.0295=1.0795 V`