Question

Total number of unpaired electrons present in Co3+ (Atomic number = 27)
is​

Answer 1

Answer:

A gaseous Co3+ ion in the ground state has four unpaired electrons.

Explanation:

The electron configuration of a cobalt atom is

Co:[Ar]4s^2 3d^7

The orbital diagram looks like this :

When we remove electrons to form the

Co3+ ion, we first remove the two 4s electrons and then one of the 3d electrons.

The new electron configuration becomes

Co3+:[Ar]3d^6

The new orbital diagram looks like this:

The Co3+ ion has four unpaired electrons.

hope this helps you!

Answer 2

Explanation:

To Find :-

• Total number of unpaired electrons present in Co³+

Solution :-

Electronic configuration of Co is :-

1s² 2s² 2p^6 3s² 3p^6 4s² 3d^7 or [Ar] 3d^7 4s²

Now,

As we know that :-

• Electron goes from the outermost subshell.

It means,

Electron goes from 4s subshell then 3d subshell.

Here, Its 3+ charge on Co it means, 3 electron is lose by Co.

Electronic configuration of Co³+ is

[Ar] 3d^6

And we know that, d-block have 5 shell and it has maximum ability to contains 10 electron, and here it's 6 electron in outermost shell.

According to Hund’s rule electron are filled after in all subshell after it's half filled.

It means,

5 Electron are filled in 5 boxes then again 1 remaining electron are filled.

Then, we see that Co³+ contains 4 unpaired electron and it's paramagnetic (bcoz it contain unpaired electron. )

Orbital diagram of Co³+ :-

( Refer to the attachment. )