Ncert Exercises & Solutions

Out of $C u_{2} C l_{2} a n d C u C l_{2},$ which is more stable and why?

NEETprep Answer: Among

C u_{2} C I_{2} a n d C u C I_{2}, C u C I_{2}

is more stable.

Stability of complex can be explained on the basis of stability of oxidation state of copper.

Stability of

C u^{2 +} (a q)

rather than

C u^{2 +} (a q)

is due to much more negative value of

[∆_{h y d} H^{θ} o f C u^{2 +} (a q)]

than

C u^{+}

which more than compensates for the second ionisation enthalpy of Cu.