Question

For principle quantum number n = 4, the total number of orbitals having l = 3 is:

• A. 3
• B. 5
• C. 7
• D. 9

Answer 1

The correct option is C 7

Principal quantum number n = 4 and azimuthal quantum number l = 3.
For n = 4, l = 3 subshell is 4f
Magnetic quantum number m ranges from $-l$ to $+l$
Total number of orbitals = $2l+1$
For l = 3, m = $(2\times 3+1$) = 7