Poly `-beta` - hydroxybutyrate - co`-beta -` hydroxyvalerate (PHBV ) is a copolymer of ________.

Options

A. 3-hydroxybutanoic acid and 4-hydroxypentanoic acid
B. 2-hydroxybutanoic acid and 3-hydroxypentanoic acid
C. 3-hydroxybutanoic acid and 3-hydroxypentanoic acid
D. 3-hydroxybutanoic acid and 2-hydroxypentanoic acid

Explanation

To determine the monomers that make up the copolymer Poly β-hydroxybutyrate-co-β-hydroxyvalerate (PHBV), we can follow these steps:

### Step 1: Identify the Structure of PHBV
PHBV is a copolymer formed from two different monomers. To understand this, we need to visualize the repeating units of the polymer.

### Step 2: Determine the Monomers
The repeating units of PHBV consist of:
1. **β-Hydroxybutyrate**: This is derived from butanoic acid (4 carbons) with a hydroxyl group (-OH) on the β-carbon. The structure can be represented as:
- **Monomer 1**: 3-hydroxybutanoic acid (C4H8O3)

2. **β-Hydroxyvalerate**: This is derived from valeric acid (5 carbons) with a hydroxyl group (-OH) on the β-carbon. The structure can be represented as:
- **Monomer 2**: 3-hydroxyvaleric acid (C5H10O3)

### Step 3: Naming the Monomers
- For **3-hydroxybutanoic acid**:
- The main chain has 4 carbons (butanoic acid).
- The hydroxyl group is on the 3rd carbon.

- For **3-hydroxyvaleric acid**:
- The main chain has 5 carbons (valeric acid).
- The hydroxyl group is on the 3rd carbon.

### Step 4: Conclusion
Thus, the copolymer PHBV is formed from the following two monomers:
- 3-hydroxybutanoic acid
- 3-hydroxyvaleric acid

### Final Answer
Poly β-hydroxybutyrate-co-β-hydroxyvalerate (PHBV) is a copolymer of **3-hydroxybutanoic acid and 3-hydroxyvaleric acid**.

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