Question

Why zn shows only +2 oxidation state

Answer 1

Zinc is more likely to lose its 4s electrons first, before dropping its 3d electrons. There are only 2 4s electrons to be lost, so zinc has an oxidation state of +2. Furthermore, it is unlikely zinc will lose more than its 4s electrons because the 3d orbital is filled and quite stable. Thus, it has a possible 2+ oxidation state. 

Answer 2

Answer:

Explanation:

Since Zn have Configuration- [Ar]3d^104s2.

So by loosing 2 electrons from outer most shell I.e. 4s it become stable so by loosing the electrons it become Zn2+ .

It s hard to loose the electron from 3d subshell because it is fully filled which make it stable.

Hence Zn can only loose 2electrons and become Zn2+.