Question

Which of the following does not show variable valency?
1) Iron
2) Silver
3) Gold
4) Copper

Answer 1

Explanation:

The electronic configuration of zinc is [Ar]3d104s2.

It can only lose two electrons from the 4s orbital and show +2 

oxidation state. 

It does not show variable valency. 

However, all other transition metals like Mn, Fe, Cr have partially filled d orbitals and hence, show variable valency.

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