Orientation of orbitals is given by

Options

A. Magnetic quantum number
B. Spin quantum number
C. Azimuthal quantum number
D. Principal quantum number

Answer

To solve the question regarding which quantum number describes the orientation of orbitals, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Quantum Numbers**:
- The four quantum numbers are:
- Principal Quantum Number (n)
- Azimuthal Quantum Number (l)
- Magnetic Quantum Number (m)
- Spin Quantum Number (s)

2. **Identify the Role of Each Quantum Number**:
- **Principal Quantum Number (n)**: This quantum number indicates the size and energy level of the electron shell. It does not provide information about the orientation of orbitals.
- **Azimuthal Quantum Number (l)**: This quantum number defines the shape of the orbital (s, p, d, f) but does not specify the orientation.
- **Magnetic Quantum Number (m)**: This quantum number specifically describes the orientation of the orbital in space. It can take values from -l to +l, indicating the different orientations of the orbitals within a given subshell.
- **Spin Quantum Number (s)**: This quantum number indicates the direction of the electron's spin, not the orientation of the orbital.

3. **Conclusion**:
- Since the question asks for the quantum number that describes the orientation of orbitals, the correct answer is the **Magnetic Quantum Number (m)**.

### Final Answer:
The orientation of orbitals is given by the **Magnetic Quantum Number (m)**.

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