Question

The number of unpaired electron(s) is/are present in tripositive titanium ion is:

Answer 1

Hint: We know that unpaired electron is an electron which accommodates an orbital of an atom instead of part of pairs of electrons. We can determine the number of unpaired electrons with the help of electronic configuration. We also have to observe the orbital that comes at the last in the configuration.

Complete step by step answer:
We can obtain the unpaired electrons with help of electronic configuration. We know that the order of filling orbitals is $1s,2s,2p,3s,3p,4s,3d,4p,5s,4d$ and so.
While writing the electronic configuration, the focus is mainly on the principal quantum number and azimuthal quantum number. We know that electronic configuration is based on aufbau principle. Aufbau principle states that electrons occupy the orbitals in the increasing order of energy levels and the orbitals with lowest energy are occupied first.
We can obtain the unpaired electrons by,
Determining the atomic number
Writing the electronic configuration
If we notice the orbitals have an odd number of electrons then the atom would have unpaired electrons.
Now getting back to the question, we know that the atomic number of titanium is 22.
We can write the electronic configuration of titanium is $1{s^2}2{s^2}2{p^6}3{s^2}3{p^6}3{d^2}4{s^2}$.
Since it is given as a tripositive titanium ion, three electrons are removed. So the electronic configuration of tripositive titanium ion becomes $1{s^2}2{s^2}2{p^6}3{s^2}3{p^6}3{d^1}$.
On looking into the electronic configuration of tripositive titanium ions, we can see that there is one unpaired electron in $3d$ orbital.

So, the number of unpaired electron tripositive titanium ions is one. .

Note: In organic chemistry, we can say that unpaired electrons are known as radical, and they play an important role in reaction pathways. Based on Hund’s rule, the unpaired electron spins are aligned parallel and because the molecules exhibit paramagnetic properties. Atoms and ions of lanthanides and actinides are some of the examples of stable unpaired electrons. $G{d^{3 + }}$ and $C{m^{3 + }}$ have seven unpaired electrons and these ions contain the largest number of unpaired electrons.