Question

How many valence electrons do Zinc and Iron have? Please explain how you calculated this.

Answer 1

These Fe and Zn both are transition metals which have incomplete d subshells. These atoms can use their d electrons for bonding thus the total valence electrons for a transition metal are the ns and (n-1)d electrons.

The electronic confuguration of Fe and Zn are as follows:

Fe : 26 [Ar] 3d6 4s2

Now we calcualte the valance electron for Fe which are ns and (n-1)d electrons mean total 8 electrons.

Zn : 30 [Ar] 3d10 4s2

Now we calcualte the valance electron for Zn which are ns and (n-1)d electrons mean total 12 electrons. But in thid case n-1 d shell conpletely filled thus these can not used fro bonding hence the valance electron for Zn is 2.