Which of the following is indicated by the magnetic quantum number ?

Options

A. Size
B. Shape
C. Spatial orientation
D. Spin

Answer

To solve the question regarding what is indicated by the magnetic quantum number (ml), we can follow these steps:

### Step-by-Step Solution:

1. **Understand Quantum Numbers**:
Quantum numbers are values that describe the energy levels and positions of electrons in an atom. There are four types of quantum numbers: principal (n), azimuthal (l), magnetic (ml), and spin (ms).

2. **Identify the Magnetic Quantum Number (ml)**:
The magnetic quantum number (ml) is associated with the orientation of the orbital in which an electron resides. It can take on integer values based on the azimuthal quantum number (l).

3. **Range of Magnetic Quantum Number**:
The values of ml can range from -l to +l, including zero. For example, if l = 2 (which corresponds to a d-orbital), then ml can take values of -2, -1, 0, +1, and +2.

4. **Interpretation of ml**:
The magnetic quantum number indicates the orientation of the orbital in a magnetic field. Different values of ml correspond to different orientations of the electron cloud in space.

5. **Conclusion**:
Therefore, the magnetic quantum number (ml) indicates the spatial orientation of the electron's orbital.

### Final Answer:
The magnetic quantum number (ml) indicates the spatial orientation of the electron.

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