Question

$Cu^+$ ion is not stable in aqueous solution because

• A. second ionisation enthalpy of copper is less than the first ionisation enthalpy
• B. large value of second ionisation enthalpy of copper is compensated by much more negative hydration energy of $Cu^{2+}_{(aq)}$
• C. hydration energy of $Cu^{+}_{(aq)}$ is much more negative than that of $Cu^{2+}_{(aq)}$
• D. many copper $(I)$ compounds are unstable in aqueous solution and undergo disproportion ation reaction

Answer 1

Answer: (B)

Cu ion is not stable in aqueous solution because large value of second ionisation enthalphy of copper is compenscited by much more negative hydration energy of $Cu _{\text {(aq.) }}^{2+}$