Assertion : Water kept in an open vessel will quickly evaporate on the surface of the moon.
Reason : The temperature at the surface of the moon is much higher than boiling point of the water.

Explanation

To solve the question, we need to analyze both the assertion and the reason provided.

### Step 1: Analyze the Assertion
The assertion states that "Water kept in an open vessel will quickly evaporate on the surface of the moon."

- On the moon, the atmospheric pressure is significantly lower than that on Earth. This low pressure allows water to evaporate more quickly, even at lower temperatures. Thus, the assertion is **correct**.

### Step 2: Analyze the Reason
The reason states that "The temperature at the surface of the moon is much higher than the boiling point of the water."

- The average temperature on the moon's surface can reach up to approximately 123 degrees Celsius during the day. However, the boiling point of water at standard atmospheric pressure (1 atm) is 100 degrees Celsius. Since the moon has a very low atmospheric pressure, the boiling point of water is also lower than 100 degrees Celsius. Therefore, the assertion that the temperature is much higher than the boiling point of water is **incorrect**.

### Conclusion
- The assertion is correct: Water will evaporate quickly on the moon due to low atmospheric pressure.
- The reason is incorrect: The temperature on the moon is not necessarily higher than the boiling point of water under the moon's conditions.

### Final Answer
- The assertion is correct, but the reason is incorrect.

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