Define the term Branched chain hydrocarbons

Explanation

**Step-by-Step Text Solution:**

1. **Definition of Branched Chain Hydrocarbons**: Branched chain hydrocarbons are hydrocarbons that contain one or more branches in their carbon chain. These branches consist of smaller chains of carbon atoms that are attached to the main carbon chain.

2. **Understanding the Structure**: In a branched chain hydrocarbon, the main carbon chain is referred to as the "parent chain," and the smaller chains attached to it are called "branches." These branches can be represented as alkyl groups.

3. **Examples of Alkyl Groups**: Common examples of alkyl groups that can create branches include propyl (C3H7) and butyl (C4H9) groups.

4. **Illustration of Branched Structures**:
- For example, isopropyl is a branched structure derived from the propyl group. Its structure can be represented as:
```
CH3
|
CH
|
CH3
```
- Similarly, the secondary butyl group can be illustrated as:
```
CH3
|
CH2
|
CH
|
CH3
```

5. **Conclusion**: In summary, branched chain hydrocarbons are characterized by the presence of branches (alkyl groups) attached to a parent carbon chain, which can significantly influence the properties and reactivity of the compound.

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