Question

Indicate the number of unpaired electrons in: Kr.

Answer 1

Step 1: Writing the electronic configuration

atomic number of Kr- 36, The electronic configuration of Krypton is: $1{\mathrm{s}}^{2}2{\mathrm{s}}^{2}2{\mathrm{p}}^{6}3{\mathrm{s}}^{2}3{\mathrm{p}}^{6}4{\mathrm{s}}^{2}3{\mathrm{d}}^{10}4{\mathrm{p}}^6$

Thus we can see that it has 8 valence electrons, in its outermost shell.

Step 2: Calculating the unpaired electrons

In Krypton, the 4p-subshell has 6 electrons in it and the 3d-subshell orbital has 10 electrons in it

Thus we can see that all the orbitals of Krypton are completely filled, hence there are no unpaired electrons present in it.

This is because Krypton is a noble gas; all noble have completely filled orbitals and thus have no unpaired electrons.

Therefore, Krypton has no unpaired electrons present in it.