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(A) : The vulcanised rubber has greater ...

(A) : The vulcanised rubber has greater elasticity and tensile strength than crude rubber
(R) : Sulphur cross-links are developed

A

Both (A) and (R) are true and (R) is the correct explanation of (A)

B

Both (A) and (R) are true (R) is not the correct explanation of (A)

C

(A) is true but (R) is false

D

(A) is false but (R) is true

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question, we need to analyze both the assertion and the reason provided: **Assertion (A):** The vulcanized rubber has greater elasticity and tensile strength than crude rubber. **Reason (R):** Sulphur cross-links are developed. ### Step 1: Understanding the Assertion - **Vulcanized Rubber vs. Crude Rubber:** - Crude rubber, also known as natural rubber, has certain limitations. It becomes soft at high temperatures (above 335 K) and brittle at low temperatures (below 283 K). - Vulcanization is a process that enhances the properties of rubber, making it more suitable for various applications, especially in tires and other products requiring durability. ### Step 2: Understanding the Reason - **Role of Sulphur in Vulcanization:** - The process of vulcanization involves heating crude rubber with sulphur at temperatures between 373 K to 415 K. - During this process, sulphur forms cross-links between the polymer chains of rubber. - These cross-links improve the elasticity and tensile strength of the rubber, making it less prone to deformation and more durable. ### Step 3: Analyzing the Relationship - **Connection Between Assertion and Reason:** - The assertion states that vulcanized rubber has greater elasticity and tensile strength than crude rubber, which is true. - The reason explains that this improvement is due to the formation of sulphur cross-links, which is also true. - Since the reason directly explains why the assertion is true, we can conclude that both the assertion and reason are correct, and the reason is the correct explanation of the assertion. ### Conclusion - Based on the analysis, the correct answer is that both the assertion and reason are true, and the reason is the correct explanation of the assertion. ### Final Answer: **Option 1:** Both assertion and reason are true, and reason is the correct explanation of assertion. ---
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