Question

What is the total number of orbitals and electrons for

(a) n=3

(b) l=2

Answer 1

In the third shell (n=3), we have:
The 3s orbital
The 3p orbitals
The 3d orbitals.
The number of orbitals in a shell is the square of the principal quantum number: 12 = 1, 22 = 4, 32 = 9. There is one orbital in an s subshell (l = 0), three orbitals in a p subshell (l = 1), and five orbitals in a d subshell (l = 2)
mℓ=−2,−1,0,+1,+2