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Assertion : Thermoplastics become hard o...

Assertion : Thermoplastics become hard on heating and soft on cooling.
Reason : Themoplastics are cross - linked polymers which are soluble in many organic solvents.

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 solve the question, we need to analyze both the assertion and the reason provided. ### Step 1: Analyze the Assertion The assertion states: "Thermoplastics become hard on heating and soft on cooling." - **Understanding Thermoplastics**: Thermoplastics are a type of polymer that softens when heated and hardens when cooled. This behavior is due to the weak intermolecular forces between the polymer chains, which allow them to move more freely when heated. - **Conclusion on Assertion**: The assertion is incorrect because thermoplastics actually become soft on heating and hard on cooling. ### Step 2: Analyze the Reason The reason states: "Thermoplastics are cross-linked polymers which are soluble in many organic solvents." - **Understanding Cross-linked Polymers**: Cross-linked polymers are typically thermosetting plastics, not thermoplastics. Thermoplastics have linear or branched structures and do not have cross-linking. They are not necessarily soluble in many organic solvents. - **Conclusion on Reason**: The reason is also incorrect because it mischaracterizes thermoplastics as cross-linked polymers. ### Step 3: Final Conclusion Since both the assertion and the reason are incorrect, we can conclude that the correct answer is: - **Both the assertion and the reason are false.** ### Final Answer The correct option is D: Both the assertion and reason are false. ---
To solve the question, we need to analyze both the assertion and the reason provided. ### Step 1: Analyze the Assertion The assertion states: "Thermoplastics become hard on heating and soft on cooling." - **Understanding Thermoplastics**: Thermoplastics are a type of polymer that softens when heated and hardens when cooled. This behavior is due to the weak intermolecular forces between the polymer chains, which allow them to move more freely when heated. - **Conclusion on Assertion**: The assertion is incorrect because thermoplastics actually become soft on heating and hard on cooling. ### Step 2: Analyze the Reason ...
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