Which of the following solutions shows positive deviation from Raoult's law ?

Options

A. Acetone + Aniline
B. Acetone + Ethanol
C. Water+ Nitric acid
D. Chloroform + Benzene

Explanation

To determine which of the given solutions shows a positive deviation from Raoult's law, we need to understand the concepts of ideal and non-ideal solutions, as well as the conditions that lead to positive and negative deviations.

### Step-by-Step Solution:

1. **Understand Raoult's Law**:
Raoult's law states that the partial vapor pressure of each component in an ideal solution is directly proportional to its mole fraction in the solution. Ideal solutions follow this law perfectly.

2. **Identify Types of Solutions**:
- **Ideal Solutions**: Follow Raoult's law completely.
- **Non-Ideal Solutions**: Do not follow Raoult's law and can show either positive or negative deviations.
- **Positive Deviation**: Occurs when the solute-solute and solvent-solvent interactions are stronger than the solute-solvent interactions.
- **Negative Deviation**: Occurs when the solute-solvent interactions are stronger than the solute-solute and solvent-solvent interactions.

3. **Analyze the Given Solutions**:
- We need to evaluate the interactions between the components of each solution provided in the options.
- **Acetone + Ethanol**: Acetone (CH3C(=O)CH3) and ethanol (CH3CH2OH) have weaker hydrogen bonding interactions compared to their own interactions (acetone-acetone and ethanol-ethanol). Therefore, this solution shows a positive deviation.
- **Acetone + Aniline**: Acetone and aniline (C6H5NH2) will show negative deviation due to stronger hydrogen bonding between aniline and acetone.
- **Water + Nitric Acid**: This combination also shows negative deviation due to strong interactions between water and nitric acid.
- **Chloroform + Benzene**: This solution shows negative deviation as well, due to the stronger interactions between chloroform and benzene compared to their interactions with each other.

4. **Conclusion**:
After analyzing the interactions, the solution that shows a positive deviation from Raoult's law is **Acetone + Ethanol**.

### Final Answer:
The solution that shows positive deviation from Raoult's law is **Acetone + Ethanol**.