Impossible orbital among the following is

Options

A. 2s
B. 3f
C. 2p
D. 4d

Explanation

To determine which orbital is impossible among the given options, we need to apply the rules governing quantum numbers. The principal quantum number (n) and the azimuthal quantum number (l) must satisfy certain conditions:

1. The value of l must be less than n (l < n).
2. The value of l can take on integer values from 0 to (n-1).

Given this, let's analyze the options step by step:

### Step-by-Step Solution:

1. **Understanding Quantum Numbers**:
- The principal quantum number (n) indicates the energy level of an electron in an atom.
- The azimuthal quantum number (l) indicates the shape of the orbital and can take values from 0 to (n-1).

2. **Analyzing Each Option**:
- **Option A**: n = 2, l = 0 (s orbital)
- Here, l = 0 is valid since l can be 0 to (n-1) which is 1 for n=2. Therefore, this orbital is possible.
- **Option B**: n = 3, l = 3 (f orbital)
- Here, l cannot be equal to n. Since l must be less than n, this is not a valid orbital. Therefore, this orbital is impossible.
- **Option C**: n = 2, l = 1 (p orbital)
- Here, l = 1 is valid since l can be 0 to (n-1) which is 1 for n=2. Therefore, this orbital is possible.
- **Option D**: n = 4, l = 2 (d orbital)
- Here, l = 2 is valid since l can be 0 to (n-1) which is 3 for n=4. Therefore, this orbital is possible.

3. **Conclusion**:
- The only impossible orbital among the options is **Option B: 3f**.

### Final Answer:
The impossible orbital among the following is **3f**.