Which one of the following orbitals is spherical in shape ?

Options

A. 4s
B. 3p-oribital
C. 3d
D. 4f

Answer

To determine which of the following orbitals is spherical in shape, let's analyze the options provided: 4s, 3p, 3d, and 4f.

### Step-by-Step Solution:

1. **Understanding Orbital Types**:
- Orbitals are classified based on the azimuthal quantum number (l).
- The types of orbitals are:
- **s orbitals (l = 0)**: Spherical in shape.
- **p orbitals (l = 1)**: Dumbbell-shaped.
- **d orbitals (l = 2)**: Cloverleaf shape (double dumbbell).
- **f orbitals (l = 3)**: More complex and diffused in shape.

2. **Identifying the Given Orbitals**:
- **4s orbital**: This is an s orbital (l = 0).
- **3p orbital**: This is a p orbital (l = 1).
- **3d orbital**: This is a d orbital (l = 2).
- **4f orbital**: This is an f orbital (l = 3).

3. **Determining the Shape of Each Orbital**:
- **4s orbital**: Spherical shape.
- **3p orbital**: Dumbbell shape.
- **3d orbital**: Cloverleaf shape.
- **4f orbital**: Diffused shape.

4. **Conclusion**:
- Among the options provided, the only orbital that is spherical in shape is the **4s orbital**.

### Final Answer:
The orbital that is spherical in shape is **4s**.

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