`Cu^(+)` disproportionate to `Cu^(2+)` and elemental copper in solution.

(a) Why are Zn^(2+) salts white while Cu^(2+) salts are blue ? (b) What is meant by 'disproportionation' ? Write the disproportionation reaction of Cu^+ in aqueous solution.

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

Statement-1: Many copper (I) compound are unstable in aqueous solution and undergo disproportionation. Statement-2: Cu^(2+) I mre stable than Cu^(+) because of much more negative Delta_(hyd)H^(@) of Cu^(2+) than Cu^(+) , which more than compensates for seconds ionisation enthalpy.

The oxidation state of Cu and Fe in copper pyrities is respectively:

Assertion: Aquated copper(I) cation undergoes disproportionation as: 2Cu^(+)(aq) to Cu^(2+)(aq)+Cu Reason: Hydration energy of Cu^(2+) is higher than that of Cu^(+) which compensates second ionisation energy of Cu.

Assertion Cu^(o+) ion is unstable in aqueous solution, whereas Fe^(2+) ion is stable Cu^(o+) disproportionate in aqueous solution .

The reduction potential diagram for Cu in acid solution is : Calculate X . Does Cu^(+) disproportionate in solution ?