Which of the following forms is an ideal solution?

Options

A. Ethyl bromide + Ethyl iodide
B. Ethyl alcohol + water
C. Chloroform + Benzene
D. Benzene + Toluene

Answer

To determine which of the following forms an ideal solution, we need to understand the characteristics of ideal solutions. An ideal solution is one where the interactions between the solute and solvent molecules are similar to the interactions between the solute-solute and solvent-solvent molecules.

### Step-by-Step Solution:

1. **Definition of Ideal Solution**:
- An ideal solution is characterized by the following:
- The enthalpy of mixing (ΔH_mixing) is equal to 0, meaning no heat is absorbed or released during the mixing process.
- The change in volume upon mixing (ΔV_mixing) is also equal to 0, indicating no net change in volume.
- The interactions between solute-solute, solvent-solvent, and solute-solvent must be similar.

2. **Analyzing the Options**:
- **Option A: Ethyl Bromide and Ethyl Iodide**:
- Both are similar types of molecules (alkyl halides) and will have similar dipole-dipole interactions. Therefore, they can form an ideal solution.

- **Option B: Ethyl Alcohol and Water**:
- Ethyl alcohol (ethanol) and water have strong hydrogen bonding. The interactions differ when mixed compared to when they are separate, thus they do not form an ideal solution.

- **Option C: Chloroform and Benzene**:
- Chloroform is polar while benzene is non-polar. The difference in polarity leads to different types of interactions, so they do not form an ideal solution.

- **Option D: Benzene and Toluene**:
- Both benzene and toluene are non-polar aromatic hydrocarbons. The interactions between them are similar to their respective interactions with themselves, making them capable of forming an ideal solution.

3. **Conclusion**:
- Based on the analysis, the options that form ideal solutions are:
- **Option A: Ethyl Bromide and Ethyl Iodide**
- **Option D: Benzene and Toluene**

### Final Answer:
The ideal solutions are **Option A (Ethyl Bromide and Ethyl Iodide)** and **Option D (Benzene and Toluene)**.