Total number of orbitals present in M shell is

Explanation

To determine the total number of orbitals present in the M shell, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Principal Quantum Number (n)**:
- The M shell corresponds to the principal quantum number \( n = 3 \).

2. **Determine the Azimuthal Quantum Number (l)**:
- The azimuthal quantum number \( l \) can take values from \( 0 \) to \( n-1 \).
- For \( n = 3 \), the possible values of \( l \) are:
- \( l = 0 \) (s subshell)
- \( l = 1 \) (p subshell)
- \( l = 2 \) (d subshell)

3. **Count the Orbitals in Each Subshell**:
- Each subshell has a specific number of orbitals:
- The s subshell (\( l = 0 \)) has **1 orbital**.
- The p subshell (\( l = 1 \)) has **3 orbitals**.
- The d subshell (\( l = 2 \)) has **5 orbitals**.

4. **Calculate the Total Number of Orbitals**:
- To find the total number of orbitals in the M shell, we add the number of orbitals from each subshell:
\[ \text{Total orbitals} = 1 \, (\text{s}) + 3 \, (\text{p}) + 5 \, (\text{d}) = 9 \]

5. **Conclusion**:
- Therefore, the total number of orbitals present in the M shell is **9**.