Raoult's low is obeyed by each constituent of binary liquid solution when :

Options

A. the forces of attraction between like molecules are greather than those between unlike molecules
B. the forces of attraction between like molecules are smaller than those between unlike molecules
C. the forces of attraction between like molecules are identical with those between unlike molecules
D. the volumn occupid by unlike molercules are different

Answer

**Step-by-Step Solution:**

1. **Understanding Raoult's Law**: Raoult's law states that in an ideal solution, the partial vapor pressure of each component is directly proportional to its mole fraction in the solution. This law is applicable when the interactions between the molecules of the different components are similar.

2. **Identifying Ideal Solutions**: For Raoult's law to be obeyed by each constituent of a binary liquid solution, the solution must be ideal. An ideal solution is one where the intermolecular forces of attraction between the molecules of the same type (like molecules) are equal to those between different types of molecules (unlike molecules).

3. **Conditions for Raoult's Law**: The law is obeyed when:
- The forces of attraction between like molecules (A-A and B-B) are similar to the forces of attraction between unlike molecules (A-B).
- This condition ensures that the behavior of the solution is predictable and follows the linear relationship defined by Raoult's law.

4. **Conclusion**: Therefore, Raoult's law is obeyed by each constituent of a binary liquid solution when the forces of attraction between like molecules are identical to those between unlike molecules.

5. **Correct Answer**: The correct answer to the question is that Raoult's law is obeyed when the forces of attraction between like molecules are identical with those of the unlike molecules.

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