The repeating units of PCTEF is

Options

A. `CF_(2)=CF_(2)`
B. `CH_(2)=CH_(2)`
C. `CF_(3)=CF_(3)`
D. `FCIC=CF_(2)`

Explanation

To determine the repeating units of PCTEF (Polychlorotriphloroethylene), we can follow these steps:

### Step 1: Understand the Full Name
The full name of PCTEF is Polychlorotriphloroethylene. This indicates that the polymer is derived from the monomer trichloroethylene, which contains carbon and chlorine atoms.

**Hint:** The name of the polymer often gives clues about its structure and the elements involved.

### Step 2: Identify the Monomer Structure
The monomer for PCTEF is trichloroethylene, which has the chemical formula C2HCl3. When we look at the structure, we can see that it consists of carbon atoms bonded to chlorine and hydrogen.

**Hint:** Look for the chemical structure of the monomer to understand how the repeating units will be formed.

### Step 3: Determine the Repeating Unit
In the case of PCTEF, the repeating unit will consist of the carbon atoms and the substituents (chlorine and fluorine) that replace the hydrogen atoms in the monomer. The repeating unit can be represented as:
- Carbon (C)
- Two Fluorine (F) atoms
- One Chlorine (Cl) atom

The general structure of the repeating unit can be denoted as:
\[ \text{CF}_2 - \text{CCl} \]

This indicates that each repeating unit consists of a carbon-carbon bond with two fluorine atoms and one chlorine atom attached to the second carbon.

**Hint:** Focus on how the atoms are arranged in the repeating unit and ensure to include all substituents.

### Step 4: Write the Final Repeating Unit
The final repeating unit for PCTEF can be summarized as:
\[ -\text{CF}_2 - \text{CCl}- \]

This notation indicates that the polymer consists of a chain of repeating units of CF2 and CCl.

**Hint:** Make sure to include the correct bonds and atoms in your final representation of the repeating unit.

### Conclusion
The repeating units of PCTEF (Polychlorotriphloroethylene) can be represented as \(-\text{CF}_2 - \text{CCl}-\).