Question

How many unpaired electrons are in a zinc atom?

Answer 1

In the above question, it is asked about the number of unpaired electrons in a zinc atom. For this, we have to first look at the atomic number of zinc atoms. Then we have to write the electronic configuration and looking at the electronic configuration we can infer whether zinc has unpaired electrons or not.

Complete step by step solution
The atomic number of Zinc is 30. The atomic number denotes the number of protons in an atom. In a neutral atom, the number of protons is equal to electrons. In charged ions, the number of electrons is not equal to the number of protons because of gain or loss of electrons.
Since, zinc is a neutral atom, so the number of electrons present in it is 30. The electronic configuration of zinc is ${\text{1}}{{\text{s}}^{\text{2}}}{\text{2}}{{\text{s}}^{\text{2}}}{\text{2}}{{\text{p}}^{\text{6}}}{\text{3}}{{\text{s}}^{\text{2}}}{\text{3}}{{\text{p}}^{\text{6}}}{\text{4}}{{\text{s}}^{\text{2}}}{\text{3}}{{\text{d}}^{{\text{10}}}}$
We can see that the s and p orbital of all energy levels are filled and hence, there are no unpaired electrons.

Additional Information
Zinc is unusually stable because of the lack of unpaired electrons. Steel nails are often coated with zinc in order to protect the nails from rusting, because zinc is relatively unreactive.
The 3d electrons are technically part of the third electron shell. The filled 3d orbitals become part of the third shell and are stable. The last 4s energy shells take part in bond formation.

Note
Zinc is the 24th most abundant element in Earth’s crust and has five stable isotopes.
Zinc has a self-healing mechanism in it.
Unpaired electrons are present if the electronic configuration of that element is odd.