A : Polypropylene is an addition polymer.
R:Addition polymerization occurs among molecules which contain double bonds.

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 solve the question, we need to analyze both the assertion and the reason provided.

**Assertion (A): Polypropylene is an addition polymer.**
**Reason (R): Addition polymerization occurs among molecules which contain double bonds.**

### Step-by-Step Solution:

1. **Understanding Polypropylene**:
- Polypropylene is a type of plastic that is made from the polymerization of propylene monomers.
- The chemical structure of propylene is CH2=CH-CH3, which contains a double bond between the first two carbon atoms.

2. **Defining Addition Polymerization**:
- Addition polymerization is a process where unsaturated monomers (those containing double or triple bonds) react to form a polymer without the loss of any small molecules (like water or methanol).
- This process involves the breaking of the double bonds in the monomers, allowing them to link together to form long chains.

3. **Analyzing the Assertion**:
- Since polypropylene is formed from the polymerization of propylene, and propylene contains a double bond, we can conclude that polypropylene is indeed an addition polymer.
- Therefore, the assertion that "Polypropylene is an addition polymer" is **true**.

4. **Analyzing the Reason**:
- The reason states that "Addition polymerization occurs among molecules which contain double bonds."
- This is also true, as addition polymerization specifically requires unsaturated monomers (those with double or triple bonds) to initiate the polymerization process.

5. **Conclusion**:
- Both the assertion and the reason are true, and the reason correctly explains the assertion.
- Therefore, the correct answer is that both the assertion and the reason are true, and the reason is a correct explanation of the assertion.

### Final Answer:
Both the assertion and the reason are true, and the reason is a correct explanation of the assertion.

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