Which of the following organic compounds polymerize to form the polyester Dacron?

Options

A. Propylene and para`-OH(C_(6)H_(4))-OH`
B. Benzoic acid and ethanol
C. Terephthalic acid and ethylene glycol
D. Brnzoic acid and para`-OH(C_(6)H_(4))-OH`

Explanation

To determine which organic compounds polymerize to form the polyester Dacron, we can follow these steps:

### Step 1: Identify the Monomers
The first step is to identify the monomers that are used to create Dacron. Dacron is a type of polyester, and its formation involves two specific organic compounds:
- **Terephthalic Acid** (C8H6O4)
- **Ethylene Glycol** (C2H6O2)

### Step 2: Understand the Polymerization Process
Dacron is formed through a process known as condensation polymerization. In this process, the monomers combine to form a polymer while releasing a small molecule, typically water.

### Step 3: Write the Chemical Structures
- **Terephthalic Acid** can be represented as:
```
O
||
C6H4 - C - OH
|
C - OH
||
O
```
- **Ethylene Glycol** can be represented as:
```
HO - CH2 - CH2 - OH
```

### Step 4: Combine the Monomers
When ethylene glycol reacts with terephthalic acid, they undergo condensation:
- The hydroxyl (–OH) group from ethylene glycol and a hydrogen (H) from the carboxylic acid group of terephthalic acid combine to form water (H2O).
- This reaction forms an ester bond, linking the two monomers together.

### Step 5: Form the Polymer
As the reaction continues, more molecules of ethylene glycol and terephthalic acid combine, leading to the formation of long chains of Dacron. The repeating unit in the polymer can be represented as:
```
O
||
C - O - CH2 - CH2 - O - C
||
C
```
This structure continues to repeat, forming a long polymer chain.

### Step 6: Conclusion
The final conclusion is that the organic compounds that polymerize to form the polyester Dacron are **terephthalic acid and ethylene glycol**.