00:03
Here in this problem, we'll talk about the number of unpaired electrons in the ground state of cobalt and is it paramagnetic or diamagnetic.
00:14
Now, the atomic number of cobalt is 27.
00:22
Now let's write the electron configuration first.
00:27
So we'll follow this chart here.
00:30
First, there will be 1s, then 2 s, then 2p orbitals.
00:36
Then 3s and so on so first 1 s 2 s can hold maximum 2 electrons then 2 s 2 p p can hold maximum 6 electrons 2 p 6 then 3 s 2 then 4 s 2 now we have 2 2 to 4, 6, 10, 12, 18, 20 electrons used up out of 27.
01:15
So, 7 more electrons there.
01:18
So we will write 3d after 4s2 and all 7 electrons will be in the d subshell...