What is the total number of orbitals associated with the principle quantum number n-3 ?

Explanation

For n=3 the possible value of l are 0.1 and 2 Thus 3s ,3p and 3d orbitals
Now n=3 and l=0 `m_(l) =0 ` and one 3s orbitals
`l =1 m_(1) = 1 , 0 +1 ` three value = there 3p - orbitals Total orbital = (1) 3s + (3) 3p + (5) 3d - orbitals
Second method.
Number of orbitals in n orbit `=n^(2) = (3)^(2) =9`