Assertion : At constant pressure, the volume of a given mass of a gas is inversely proportional to its absolute temperature.
Reason : At absolute zero, the volume of a gas reduces to zero.

Options

A. If both Assertion and Reason are CORRECT and Reason is the CORRECT explanation of the Assertion.
B. If both Assertion and Reason are CORRECT but Reason is not the CORRECT explanation of the Assertion.
C. If Assertion is CORRECT but Reason is INCORRECT.
D. If Assertion is INCORRECT but Reason is CORRECT.

Explanation

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

### Step 1: Analyze the Assertion
The assertion states: "At constant pressure, the volume of a given mass of a gas is inversely proportional to its absolute temperature."

- According to Charles's Law, at constant pressure, the volume (V) of a gas is directly proportional to its absolute temperature (T). This can be expressed mathematically as:

\[ V \propto T \quad \text{(at constant pressure)} \]

- This means that as the temperature increases, the volume also increases, and vice versa. Therefore, the assertion is incorrect because it states that volume is inversely proportional to temperature.

### Step 2: Analyze the Reason
The reason states: "At absolute zero, the volume of a gas reduces to zero."

- Absolute zero is defined as 0 Kelvin, which is equivalent to -273.15 degrees Celsius. At this temperature, the kinetic energy of gas molecules theoretically becomes zero, leading to the conclusion that the volume of an ideal gas would also approach zero.

- This statement is correct as it aligns with the principles of gas behavior at extremely low temperatures.

### Step 3: Conclusion
- Since the assertion is incorrect and the reason is correct, we conclude that:
- Assertion: False
- Reason: True

### Final Answer
The assertion is false, while the reason is true.

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