Question

Why copper shows +2 oxidation state not +1 and why +2 is stable??​

Answer 1

because of very small energy gap between 5f, 6d and 7s sub shells. Thus, the outermost electrons get easily excited to the higher energy levels, giving variable oxidation states.

Answer 2

Explanation:

stability is proportional to Hydration enthalpy , when it reacts with H2O to form bond Cu+2 has higher H.E which shows it forms strong bond and more energy is released when a stron bond breaks. that's why Cu is found in +2 which is more stable .hope it helps