The solution showing positive deviation from ideal behaviour have ………azeotrope.

Answer

To solve the question regarding the type of azeotrope formed by solutions showing positive deviation from ideal behavior, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Ideal Behavior**:
- Ideal solutions follow Raoult's Law, where the vapor pressure of the solution is directly proportional to the mole fraction of the solvent.

**Hint**: Recall that ideal solutions have similar intermolecular forces between solute and solvent.

2. **Define Positive Deviation**:
- Positive deviation occurs when the vapor pressure of the solution is greater than that predicted by Raoult's Law. This happens when the interactions between solute-solute and solvent-solvent are weaker than the solute-solvent interactions.

**Hint**: Think about how the strength of interactions affects vapor pressure.

3. **Analyze Vapor Pressure and Boiling Point Relationship**:
- When a solution exhibits positive deviation, it means that the vapor pressure is higher than expected. A higher vapor pressure indicates that the solution will boil at a lower temperature.

**Hint**: Remember that higher vapor pressure correlates with lower boiling points.

4. **Identify Azeotrope Type**:
- Azeotropes are mixtures that have a constant boiling point and composition throughout the distillation process. In the case of positive deviation, the solution forms a minimum boiling azeotrope because the boiling point is lower than that of the pure components.

**Hint**: Consider what happens to boiling points when vapor pressures are elevated.

5. **Conclusion**:
- Therefore, the correct answer to the question is that solutions showing positive deviation from ideal behavior have a **minimum boiling azeotrope**.

### Final Answer:
The solution showing positive deviation from ideal behavior has **minimum boiling azeotrope**.