A colloidal system having a solid substance as a dispersed phase and a liquid as a dispersion medium is classified as ___________.

Options

A. solid sol.
B. gel.
C. emulsion.
D. sol.

Explanation

To solve the question, we need to classify the colloidal system based on the phases involved. Here are the steps to arrive at the answer:

### Step-by-Step Solution:

1. **Identify the Phases**: The question states that we have a solid substance as the dispersed phase and a liquid as the dispersion medium.
- Dispersed Phase (DP): Solid
- Dispersion Medium (DM): Liquid

2. **Understand Colloidal Classifications**: Colloidal systems can be classified based on the states of the dispersed phase and the dispersion medium. The common classifications include:
- **Sol**: Solid dispersed in a liquid
- **Gel**: Liquid dispersed in a solid
- **Emulsion**: Liquid dispersed in another liquid
- **Aerosol**: Solid or liquid dispersed in a gas

3. **Match the Classification**: Given that we have a solid dispersed in a liquid, we match it to the classification:
- Since the dispersed phase is solid and the dispersion medium is liquid, this corresponds to a "Sol".

4. **Final Answer**: Therefore, the colloidal system described in the question is classified as a **Sol**.

### Answer:
A colloidal system having a solid substance as a dispersed phase and a liquid as a dispersion medium is classified as **Sol**.

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