An electron is present in 4 f sub - shell . The possible values of azimuthal quantum number for this electron are :-

Options

A. 0, 1, 2, 3
B. 1 ,2, 3, 4
C. 3
D. 4

Answer

To determine the possible values of the azimuthal quantum number (L) for an electron in the 4f sub-shell, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Quantum Numbers**:
- The azimuthal quantum number (L) is associated with the shape of the orbital. It can take on integer values starting from 0 up to (n-1), where n is the principal quantum number.

2. **Identify the Principal Quantum Number (n)**:
- For the 4f sub-shell, the principal quantum number (n) is 4.

3. **Determine the Possible Values of L**:
- The possible values of L for a given n are:
- L = 0 (s sub-shell)
- L = 1 (p sub-shell)
- L = 2 (d sub-shell)
- L = 3 (f sub-shell)
- Since we are dealing with the 4f sub-shell, we specifically look for L = 3.

4. **Conclusion**:
- Therefore, the possible value of the azimuthal quantum number (L) for an electron in the 4f sub-shell is 3.

### Final Answer:
The possible value of the azimuthal quantum number for an electron in the 4f sub-shell is **3**.