Write the half reactions for the following redox reactions:
(a) `2fe_((aq.))^(3+)+2I_((aq.))^(-)rarr2Fe_((aq.))^(2+)+I_(2(aq.))`
(b) `Zn_((s))+2H_((aq.))^(+)rarrZn_((aq.))^(2+)+H_(2(g))`
(c ) `Al_((s))+3Ag_((aq.))^(3+)rarrAl_((aq))^(3+)+3Ag_((s))`

Explanation

(a) `Fe^(3+)+erarrFe^(2+)`,
`I^(-)rarr1//2I_(2)+e`
(b) `Zn rarr Zn^(2+)+2e`,
`H^(+) + e rarr 1//2H_(2)`
( c) `Al rarrAl^(3+) + 3e`
`Ag^(+) + e rarr Ag`