Make complete cell diagrams of the following cell reactions
(a). `Cd^(2)(aq)+Zn(s)toZn^(2+)(aq)+Cd(s)`
(b). `2Ag^(+)(aq)+H_(2)(g)to2H^(+)(aq)+2Ag(s)`
(c). `Hg_(2)Cl_(2)(s)+Cu(s)toCu^(2+)(aq)+2Cl^(-)(aq)+2Hg(l)`
(d). `Cu_(2)O_(7)^(2-)(aq)+14H^(+)(aq)+6Fe^(2+)(aq)to6Fe^(3+)(aq)+2Cr^(3+)(aq)+7H_(2)O(l)`

Answer

(a). `Zn|Zn^(2+)||Cd^(2+)|Cd`.
(b). `Pt,H_(2)(g)|H^(+)|||Ag^(+)|Ag`.
(c). `Cu|Cu^(2+)||Cl^(-)|Hg_(2)Cl_(2)|Hg|Pt`
(d). `Pt|Fe^(2+),|Fe^(3+)||Cr_(2)O_(7)^(2-),Cr^(3+)|Pt`

Explanation

(a). At anode `[Fe^(2+)toFe^(3+)+1e^(-)]xx5`
`underline("at cathode"(8H^(+)+MnO_(4)^(-)+5e^(-)toMn^(2+)+4H_(2)O)`
`underline(MnO_(6)^(2-)+5Fe^(2+)+8H^(+)toMn^(2+)+5Fe^(3+)+4H_(2)O)`
(b). At anode `2Cl^(-)toCl_(2)+2e^(-)`
`underline("at cathode" [Ag^(+)+2e^(e-)toAg]xx2)`
`underline(2Cl^(-)+2Ag^(+)to2Ag+Cl_(2))`