Question

Using the standard electrode potentials given in the table predict if the reaction between the following feasible.
`(a) Fe^(3+)(aq) andI^(-)(aq)`
`(b) Ag^(+)(aq) andCu(s)`
`(c )Fe^3+ (aq) and Cu(s)`
`Ag(s) and Fe^(3+) (aq)`
`(Br_(2))(aq) and Fe^(2+)(aq)`
`(d) Ag(s) and Fe^(3+)(aq)`
`(e) Br_(2)(aq) and fe^(2+)(aq)`

Answer 1

A particular reaction can be feasible if e.m.f of the cell based on the `E^(@)` values is positve. Keeping this in mind,let us predict the feasibility of the reactions.
`(a) I^(-)(aq)+Fe^(3+)(aq)rarrFe^(2+)(aq)+1//2I_(2)(g)`
`E^(@)_(cell)=0.77-0.54=0.23 V`
`(b) Cu(s)+2Ag^(+)(aq)rarrCu^(2+)(aq)rarrCu^(2+)(aq)+2Ag(s)`
`E^(@)_(cell)=(0.80-0.34)=0.46 V`
`(c )3Cu(s)+2Fe^(3+)(aq)rarr3Cu^(2+)(aq)+2Fe(s)`
`E^(@)_(cell)=(0.77-0.34)=-0.43 V`
`(d) 3Ag(s)+Fe^(3+)(aq)rarr3Ag(+)(aq)+Fe(s)`
`E^(@)_(cell)=(0.77-0.80)=-0.03 V`
`(e) Fe^(2)(aq)+Br_(2)(g)rarrFe^(3+)(aq)+2 Br^(-)(aq)`
`E^(@)_(cell)=1.08-0.77=0.31 V`