Assertion : Colloidal solution show colligative properties.
Reason : Colloidal solutions do not show brownian motion.

Options

A. Assertion and reason both are correct and the reason is correct explanation of assertion.
B. Assertion and reason both are correct but reason does not expolain assertion.
C. Assertion is correct but reason is incorrect.
D. Both assertion and reason are incorrect.

Explanation

To solve the assertion-reason question, we need to analyze both the assertion and the reason provided.

### Step 1: Analyze the Assertion
The assertion states: "Colloidal solutions show colligative properties."
- **Explanation**: Colligative properties depend on the number of solute particles in a solution, not on their identity. Colloidal solutions consist of dispersed particles that can affect the properties of the solution, similar to how solute particles do in a true solution. Therefore, colloidal solutions can exhibit colligative properties such as osmotic pressure, boiling point elevation, and freezing point depression.

**Conclusion**: The assertion is **true**.

### Step 2: Analyze the Reason
The reason states: "Colloidal solutions do not show Brownian motion."
- **Explanation**: Brownian motion refers to the random movement of particles suspended in a fluid, resulting from collisions with the molecules of the fluid. Colloidal particles are large enough to exhibit Brownian motion due to these collisions. Therefore, the statement that colloidal solutions do not show Brownian motion is incorrect.

**Conclusion**: The reason is **false**.

### Step 3: Combine the Conclusions
- The assertion is true, and the reason is false.
- Therefore, the correct answer is that the assertion is correct, but the reason is incorrect.

### Final Answer
The correct answer is: **Assertion is correct but reason is incorrect (Option C)**.

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