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Assertion : Third law of thermodynamics ...

Assertion : Third law of thermodynamics is confined to pure crystalline solids.
Reason : Theoretical arguments and practical evidences have shown that entropy of solutions and super cooled liquids is not zero at 0 K.

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

AI Generated Solution

The correct Answer is:
To analyze the given assertion and reason, we can break down the solution into several steps: ### Step 1: Understand the Third Law of Thermodynamics The Third Law of Thermodynamics states that the entropy of a perfect crystalline substance approaches zero as the temperature approaches absolute zero (0 K). This law applies specifically to pure crystalline solids. ### Step 2: Evaluate the Assertion The assertion states that "the Third Law of Thermodynamics is confined to pure crystalline solids." This is accurate because the law specifically applies to these types of materials, where the arrangement of particles is perfectly ordered. ### Step 3: Evaluate the Reason The reason provided states that "theoretical arguments and practical evidence have shown that the entropy of solutions and supercooled liquids is not zero at 0 K." This is also correct. Unlike perfect crystalline solids, solutions and supercooled liquids do not have a perfectly ordered structure, and therefore their entropy does not reach zero at absolute zero. ### Step 4: Conclusion Both the assertion and the reason are true, and the reason correctly explains the assertion. The Third Law of Thermodynamics applies to pure crystalline solids, and the behavior of other states of matter (like solutions and supercooled liquids) supports this assertion. ### Final Answer Both the assertion and reason are true, and the reason is the correct explanation of the assertion.
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