Which is incorrect?

Options

A. Isoprene is the monomer of natural rubber
B. Neoprene is monomeric unit of chloroprene
C. Vulcanisation of rubber involves-S-S- cross- linking in natural rubber
D. Neoprene rubber is resistant to aerial axidation

Answer

To determine which statement is incorrect regarding polymers, we can analyze each statement step by step.

### Step-by-Step Solution:

1. **Identify the first statement**: "Isoprene is the monomer of natural rubber."
- **Analysis**: This statement is correct. Isoprene (2-methyl-1,3-butadiene) is indeed the primary monomer that polymerizes to form natural rubber.

2. **Identify the second statement**: "Neoprene is the monomeric unit of chloroprene."
- **Analysis**: This statement is incorrect. Neoprene is actually a polymer made from the polymerization of chloroprene (2-chloro-1,3-butadiene). Therefore, neoprene cannot be a monomeric unit; it is the final polymer product.

3. **Identify the third statement**: "Vulcanization of rubber involves SS crosslinking in natural rubber."
- **Analysis**: This statement is correct. Vulcanization is a chemical process that involves crosslinking rubber molecules, typically using sulfur, which enhances the elasticity and strength of natural rubber.

4. **Identify the fourth statement**: "Neoprene rubber is resistant to aerial oxidation."
- **Analysis**: This statement is also correct. Neoprene is known for its resistance to degradation from environmental factors, including oxidation.

### Conclusion:
The only incorrect statement among the options provided is: "Neoprene is the monomeric unit of chloroprene."

### Final Answer:
The incorrect statement is: "Neoprene is the monomeric unit of chloroprene."

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