Select correct statement :

Options

A. Heats of vaporisation for a pure sovent and for a solution are similar because similar intermolecules forces between solvent molecules must be overcome in both cases
B. Entropy change between solution and vapour is smaller than the entropy change between pure solvent and vapour
C. Boiling point of the solution is larger than that of the pure solvent
D. All are correct statements

Answer

To solve the question, we need to analyze each statement provided and determine whether it is true or false based on our understanding of dilute solutions and their properties.

### Step-by-Step Solution:

1. **Evaluate the First Statement:**
- The first statement claims that the heats of vaporization for a pure solvent and for a solution are similar because the intermolecular forces between solvent molecules must be overcome in both cases.
- **Analysis:** When a solvent evaporates, the heat of vaporization is the energy required to overcome intermolecular forces. In both pure solvents and solutions, the solvent molecules must overcome similar types of intermolecular forces to transition from liquid to gas. Therefore, this statement is **true**.

2. **Evaluate the Second Statement:**
- The second statement states that the entropy change between a solution and vapor is smaller than the entropy change between a pure solvent and vapor.
- **Analysis:** When a solution evaporates, the presence of solute particles affects the number of solvent particles that can escape into the vapor phase. The entropy change (which is a measure of disorder) is indeed smaller for a solution compared to a pure solvent because the solute particles restrict the escape of solvent molecules. Thus, this statement is **true**.

3. **Evaluate the Third Statement:**
- The third statement claims that the boiling point of the solution is larger than the boiling point of the pure solvent.
- **Analysis:** This is a well-known phenomenon called boiling point elevation, which occurs when a non-volatile solute is added to a solvent. The presence of solute particles lowers the vapor pressure of the solution, requiring a higher temperature to reach the boiling point. Therefore, this statement is **true**.

4. **Conclusion:**
- Since all three statements have been evaluated and found to be true, we conclude that the correct answer is **option D**, which states that all the statements are correct.

### Final Answer:
The correct answer is **option D**: All statements are correct.