The colloidal system of a solid dispersed in liquid medium is :

Options

A. Gel
B. Homogeneous solution
C. Sol
D. Aerosol

Answer

To solve the question regarding the colloidal system of a solid dispersed in a liquid medium, we can follow these steps:

### Step 1: Understand the Components of a Colloidal System
A colloidal system consists of two main components: the dispersed phase and the dispersion medium. In this case, the dispersed phase is solid, and the dispersion medium is liquid.

### Step 2: Identify the Types of Colloids
Colloids can be classified based on the state of the dispersed phase and the dispersion medium. The common types include:
- **Sol**: Solid particles dispersed in a liquid.
- **Gel**: Liquid dispersed in a solid.
- **Emulsion**: Liquid dispersed in another liquid.
- **Aerosol**: Solid or liquid particles dispersed in a gas.

### Step 3: Analyze the Options Given
The options provided are:
1. Gel
2. Homogeneous solution
3. Sol
4. Aerosol

Since we are looking for a colloidal system where a solid is dispersed in a liquid, we can eliminate the options that do not fit this description:
- **Gel** (option 1) is a solid with liquid dispersed in it, so it does not fit.
- **Homogeneous solution** (option 2) refers to a mixture where the components are uniformly distributed, which is not a colloidal system.
- **Aerosol** (option 4) involves particles dispersed in a gas, which is also not applicable here.

### Step 4: Identify the Correct Answer
The only option that fits the description of a solid dispersed in a liquid is **Sol** (option 3). Examples of sols include paints and colloidal silica.

### Conclusion
Therefore, the correct answer to the question is **option 3: Sol**.

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