The most likely of the following mixtures to be an ideal solution is

Options

A. `NaCl-H_(2)O`
B. `C_(2)H_(5)OH-C_(6)H_(6)`
C. `C_(6)H_(16)(l)-H_(2)O`
D. `C_(6)H_(5)OH-H_(2)O`

Answer

To determine which of the following mixtures is most likely to be an ideal solution, we need to analyze the nature of each mixture provided in the options. An ideal solution is one where the interactions between the molecules of the different components are similar to the interactions between the molecules of the same component.

### Step-by-Step Solution:

1. **Understanding Ideal Solutions**:
- An ideal solution is formed when the solute-solvent interactions are similar to solute-solute and solvent-solvent interactions. This means that the enthalpy of mixing is zero and there is no volume change upon mixing.

2. **Analyzing the Options**:
- **Option 1: NaCl and H2O**:
- NaCl is a strong electrolyte that dissociates into Na⁺ and Cl⁻ ions in water. The interactions between the ions and water molecules are strong and similar to the interactions between water molecules themselves. This mixture can behave like an ideal solution.

- **Option 2: C2H5OH (Ethanol) and C6H6 (Benzene)**:
- Ethanol is polar, while benzene is non-polar. Since they are unlike substances, they do not mix well, and thus this mixture will not form an ideal solution.

- **Option 3: C6H6 (Benzene) and H2O**:
- Similar to the previous option, benzene (non-polar) and water (polar) do not mix well. This mixture will also not form an ideal solution.

- **Option 4: C6H5OH (Phenol) and H2O**:
- Phenol can form hydrogen bonds with water, leading to strong interactions that deviate from ideal behavior. Thus, this mixture will also not be an ideal solution.

3. **Conclusion**:
- After analyzing all the options, we find that **Option 1: NaCl and H2O** is the most likely to form an ideal solution because the interactions between the ions and water are similar to the interactions between water molecules.

### Final Answer:
The most likely of the following mixtures to be an ideal solution is **NaCl and H2O**.

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