A: Polybutadiene is an example of chain growth polymer.
R: Copolymerization of butadiene and styrene gives Buna-S.

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark 1.
B. If both Assertion & Reason are true but the reason is not the correct explanation of the assertion, then mark 2.
C. If Assertion is true statement but Reason is false, then mark 3.
D. If both Assertion and Reason are false statements the mark 4.

Answer

To analyze the given assertion and reason, let's break down the statements step by step:

### Step 1: Understand the Assertion
The assertion states: "Polybutadiene is an example of chain growth polymer."

- **Explanation**: Polybutadiene is formed through the polymerization of butadiene, which is an unsaturated hydrocarbon (specifically a diene). Chain growth polymerization involves the addition of monomers to form a long chain polymer. In this case, butadiene monomers link together to form polybutadiene.

### Step 2: Understand the Reason
The reason states: "Copolymerization of butadiene and styrene gives Buna-S."

- **Explanation**: Buna-S is a type of synthetic rubber that is produced by the copolymerization of butadiene and styrene. This process combines two different monomers (butadiene and styrene) to create a copolymer, which has distinct properties compared to the individual homopolymers.

### Step 3: Determine the Truth of Each Statement
- **Assertion**: True. Polybutadiene is indeed a chain growth polymer.
- **Reason**: True. The copolymerization of butadiene and styrene does produce Buna-S.

### Step 4: Analyze the Relationship Between Assertion and Reason
While both statements are true, the reason does not directly explain the assertion. The assertion is about polybutadiene being a chain growth polymer, while the reason discusses the copolymerization of butadiene and styrene, which is a different process.

### Conclusion
Both the assertion and reason are true, but the reason is not a correct explanation for the assertion. Therefore, the correct answer is that both statements are true, but the reason does not explain the assertion.

### Final Answer
Both the assertion and reason are true, but the reason is not the correct explanation for the assertion.

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