At equilibrium, the rate of dissolution of a solid solute in a volatile liquid solvent is

Options

A. less than the rate of crystallization
B. greater than the rate of crystallization
C. equal to the rate of crystallization
D. zero

Answer

To solve the question regarding the rate of dissolution of a solid solute in a volatile liquid solvent at equilibrium, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Dissolution and Crystallization**:
- When a solid solute is added to a volatile liquid solvent, it begins to dissolve. This process is known as dissolution.
- As the solute dissolves, it also reaches a point where some of the solute particles may come out of the solution, which is known as crystallization.

2. **Establishing Equilibrium**:
- At a certain concentration of the solute in the solvent, a state of equilibrium is reached. This is known as a saturated solution.
- At this point, the rate at which the solute dissolves (dissolution) is equal to the rate at which the solute crystallizes (crystallization).

3. **Analyzing the Rates**:
- At equilibrium, the processes of dissolution and crystallization occur simultaneously and at the same rate.
- Therefore, the rate of dissolution equals the rate of crystallization.

4. **Conclusion**:
- Based on the understanding that at equilibrium the rate of dissolution is equal to the rate of crystallization, we can conclude that the correct answer to the question is that the rate of dissolution of a solid solute in a volatile liquid solvent at equilibrium is **equal to the rate of crystallization**.

### Final Answer:
The rate of dissolution of a solid solute in a volatile liquid solvent at equilibrium is **equal to the rate of crystallization**.

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