Which orbitals is non-directional ?

Options

A. `s`
B. `p`
C. `d`
D. All

Explanation

To determine which orbital is non-directional among the given options (S, P, D), we can analyze the shapes and characteristics of each type of orbital.

### Step-by-Step Solution:

1. **Understanding Orbital Shapes**:
- **S Orbital**: The S orbital has a spherical shape. This means that the electron density is distributed uniformly in all directions around the nucleus. Therefore, the probability of finding an electron at a certain distance from the nucleus is the same regardless of the direction.
- **P Orbital**: The P orbital has a dumbbell shape, which means it is directional. The electron density is concentrated in two lobes on either side of the nucleus, indicating that the probability of finding an electron varies with direction.
- **D Orbital**: The D orbital has a more complex shape, often described as having a double dumbbell or cloverleaf shape. Like the P orbital, it is also directional due to its specific orientation in space.

2. **Identifying Non-Directional Orbital**:
- Since the S orbital is spherical and has uniform electron density in all directions, it is classified as non-directional.
- In contrast, both P and D orbitals are directional due to their shapes and the orientation of their electron density.

3. **Conclusion**:
- Based on the analysis, the S orbital is the only non-directional orbital among the options provided.

### Final Answer:
The non-directional orbital is the **S orbital**.

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