Monomeric unit of dacron is

Options

A. ethylene glycol
B. terephthalic acid
C. acrylonitrile
D. Both (1) and (2)

Answer

To determine the monomeric unit of Dacron, we need to identify the two components that combine to form this polymer. Dacron is a type of polyester, and its monomeric units consist of:

1. **Ethylene Glycol**: This is a diol with the chemical formula \( C_2H_6O_2 \) or more specifically, it can be represented as \( HO-CH_2-CH_2-OH \). In structural form, it can be shown as:
\[ \text{HO-CH}_2-\text{CH}_2-\text{OH} \]

2. **Terephthalic Acid**: This is a dicarboxylic acid with the chemical formula \( C_8H_6O_4 \) or more specifically, it can be represented as:
\[ \text{C}_6\text{H}_4(\text{COOH})_2 \]
In structural form, it can be shown as:
\[ \text{HOOC-C}_6\text{H}_4-\text{COOH} \]

When these two monomeric units react through a condensation reaction, they form the polymer Dacron, which is a type of polyester.

### Final Answer:
The monomeric units of Dacron are **ethylene glycol** and **terephthalic acid**.

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