Iodine is liberated in the reaction between KI and `CU^(2+)` ions but chlorine is not liberated when KCl is added to `Cu^(2+)` ions. Explain.

Explanation

KI dissolves in water to give `I^(-)` ions which are powerful reducing in nature. They reduce `Cu^(2+)` ions to `Cu^(+)` ions and `I_(2)` is thus liberated.
`2Cu^(2+)+2I^(-) to 2Cu^(+)+I_(2)`
But `Cl^(-)` ions released when KCl is dissolved in water are very weak reducing in nature and are not in a position to reduce `Cu^(2+)` ions to `Cu^(+)` ions. Therefore, chlorine is not liberated in this case.