Cu^(+) ion is not stable in aqueous solution because of disproportionation reaction. E^(@) value for disproportionation of Cu^(+) is (Given E_(Cu^(2+)//Cu^(+))^(@)=0.15,E_(Cr^(2+)//Cu)^(@)=0.34V)

Cu^(+) ion is not stable in aqueous solution because of disproportiona

1.	Cu^(+) ion is not stable in aqueous solution because of disproportionation reaction. E^(@) value for disproportionation of Cu^(+) is (Given E_(Cu^(2+)//Cu^(+))^(@)=0.15,E_(Cr^(2+)//Cu)^(@)=0.34V)
Answer» `-0.49V` `0.49V` `-0.38V` `0.38V` Solution :The REQUIRED REACTION `(Cu^(++)+Cuto2Cu^(+))` can be obtained by using the following reactions. `Cu^(++)+e^(-)toCu^(+),E_(Cu^(++)//Cu^(+))^(o)=0.15V` . . .(i) `Cu^(++)+2e^(-)toCu,E_(Cu^(++)//Cu)^(o)=0.34V` . .(ii) Multiplying eq. (i) by 2 we get `2CU^(++)+2e^(-)to2Cu^(+)`. . . (iii) `DeltaG_(1)=-nFE=-2xxFxx0.15` `Cu^(++)+2e^(-)toCu`. . . (iv) Subtract the eq. (iv) from (iii) `Cu^(++)+Cuto2Cu^(+)` `DeltaG_(3)=-nFE=-1xxFxxE^(o)` Also `DeltaG_(3)=DeltaG_(1)-DeltaG_(2)` `-1FE^(o)=(-2Fxx0.15)-(-2Fxx0.34)` `E^(o)=-0.38` this is the value of the reaction `Cu^(++)+Cuto2Cu^(+)` but the given reaction is just REVERSE of it `thereforeE_(cell)` for given reaction =+0.38V.