Which statement is correct?

Options

A. Synthesis of Buna-S needs nascent oxygen
B. Neoprene is an addition copolymer used in plastic bucket manufacturing
C. Buna-S is a synthetic and linear thermosetting polymer
D. Buna-N is a natural polymer,

Answer

To solve the question, we need to analyze each statement provided and determine which one is correct regarding the polymers mentioned. Let's go through the statements step by step.

### Step 1: Analyze the first statement
**Statement:** Buna S is a thermosetting and synthetic polymer.

**Analysis:** Buna S is actually an elastomer, which means it is a type of polymer that is flexible and can be stretched. It is not a thermosetting polymer; rather, it is a thermoplastic elastomer. Therefore, this statement is **incorrect**.

### Step 2: Analyze the second statement
**Statement:** Buna is a natural polymer.

**Analysis:** Buna N (also known as nitrile rubber) is a synthetic polymer made from the copolymerization of butadiene and acrylonitrile. It is not a natural polymer. Therefore, this statement is also **incorrect**.

### Step 3: Analyze the third statement
**Statement:** Neoprene is used to manufacture the buckets.

**Analysis:** Neoprene is a type of synthetic rubber, but buckets are typically made from high-density polyethylene (HDPE). Therefore, this statement is **incorrect**.

### Step 4: Analyze the fourth statement
**Statement:** Nascent oxygen is used in the formation of Buna N.

**Analysis:** Buna N is formed through the copolymerization of butadiene and acrylonitrile in the presence of peroxide. When peroxide decomposes, it releases nascent oxygen, which is reactive and can participate in the polymerization process. Therefore, this statement is **correct**.

### Conclusion
After analyzing all statements, we find that the **fourth statement** is the only correct one: "Nascent oxygen is used in the formation of Buna N."

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