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Assertion : All the gases should be cool...

Assertion : All the gases should be cooled below their critical temperature for liquification .
Reason : Cooling slows down the movement of molecules therefore , intermolecular forces may hold the slowly moving molecules together and the gas liquifies .

A

If both assertion and reason are true and reason is the correct explanation of assertion .

B

If both assertion and reason are true but reason is not the correct explanation of assertion .

C

If assertion is true but reason is false .

D

If both assertion and reason are false .

Text Solution

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The correct Answer is:
To solve the question, we need to analyze the assertion and reason given: ### Step 1: Understand the Assertion The assertion states: "All the gases should be cooled below their critical temperature for liquefaction." - **Explanation**: The critical temperature is defined as the temperature above which a gas cannot be liquefied, regardless of the pressure applied. Therefore, to liquefy a gas, it must be cooled below this critical temperature. ### Step 2: Evaluate the Reason The reason states: "Cooling slows down the movement of molecules; therefore, intermolecular forces may hold the slowly moving molecules together and the gas liquefies." - **Explanation**: Cooling indeed slows down the movement of gas molecules, allowing intermolecular forces (like van der Waals forces) to take effect. This can lead to liquefaction as the molecules come closer together. ### Step 3: Determine the Relationship Between Assertion and Reason - Both the assertion and reason are true. However, the reason does not fully explain the assertion because liquefaction can also occur through the application of pressure at temperatures above the critical temperature. The reason focuses solely on cooling, which is not the only factor involved in the liquefaction process. ### Conclusion - The assertion is true, and the reason is true, but the reason is not the correct explanation of the assertion. ### Final Answer The correct option is: "If both assertion and reason are true, but reason is not the correct explanation of the assertion." ---
To solve the question, we need to analyze the assertion and reason given: ### Step 1: Understand the Assertion The assertion states: "All the gases should be cooled below their critical temperature for liquefaction." - **Explanation**: The critical temperature is defined as the temperature above which a gas cannot be liquefied, regardless of the pressure applied. Therefore, to liquefy a gas, it must be cooled below this critical temperature. ### Step 2: Evaluate the Reason ...
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