Consider the following statements,
I. Adipic acid and hexamethylenediamine are the monomeric units of nylon-6,6.
II. Nylon-6,6 is a polyester.
Which of the following statement is/are incorrect? Choose the correct option.

Options

A. Only (I)
B. Only (II)
C. Both (I) and (II)
D. Neither (I) nor (II)

Answer

To solve the question, let's analyze the statements one by one and determine their correctness.

### Step 1: Analyze Statement I
**Statement I:** Adipic acid and hexamethylenediamine are the monomeric units of nylon-6,6.

- **Explanation:** Nylon-6,6 is a type of polyamide, which is formed through the condensation polymerization of hexamethylenediamine and adipic acid. The structure of adipic acid is \( \text{HOOC-(CH}_2)_4\text{-COOH} \) and hexamethylenediamine is \( \text{H}_2\text{N-(CH}_2)_6\text{-NH}_2 \). Therefore, this statement is **correct**.

### Step 2: Analyze Statement II
**Statement II:** Nylon-6,6 is a polyester.

- **Explanation:** Nylon-6,6 is not a polyester; it is a polyamide. Polyesters are formed from the reaction of diols and dicarboxylic acids, resulting in ester linkages. In contrast, polyamides like nylon-6,6 are formed from the reaction of diamines and dicarboxylic acids, resulting in amide linkages. Therefore, this statement is **incorrect**.

### Conclusion
- Statement I is **correct**.
- Statement II is **incorrect**.

Thus, the incorrect statement is Statement II.

### Final Answer
The correct option indicating the incorrect statement is **Statement II**.

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