Magnetic susceptibility of a paramagnetic substance is

Options

A. large and positive
B. small and positive
C. small and negative
D. large and negative

Explanation

To solve the question regarding the magnetic susceptibility of a paramagnetic substance, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Magnetic Susceptibility**:
- Magnetic susceptibility (χ) is a measure of how much a material will become magnetized in an applied magnetic field. It is defined as the ratio of the intensity of magnetization (M) to the magnetic field intensity (H).
- Mathematically, it is expressed as:
\[ \chi = \frac{M}{H} \]

2. **Characteristics of Paramagnetic Substances**:
- Paramagnetic substances have unpaired electrons, which means they possess a net magnetic moment.
- When an external magnetic field is applied, these magnetic moments tend to align with the field, resulting in a positive magnetization.

3. **Magnitude of Magnetic Susceptibility**:
- In paramagnetic materials, the alignment of magnetic dipoles is not complete; hence, the intensity of magnetization is relatively small.
- Therefore, the magnetic susceptibility of paramagnetic substances is positive but small.

4. **Conclusion**:
- Based on the characteristics of paramagnetic materials, we conclude that the magnetic susceptibility of a paramagnetic substance is **small and positive**.

### Final Answer:
The magnetic susceptibility of a paramagnetic substance is **small and positive**.

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