Which of the following is not a straight chain organic compound?

Options

A. Propane
B. Butane
C. Isobutane
D. Ethane

Answer

To determine which of the following compounds is not a straight chain organic compound, we will analyze each option based on their molecular structures.

### Step 1: Understand Straight Chain Organic Compounds
A straight chain organic compound is characterized by a continuous chain of carbon atoms without any branching or side chains.

### Step 2: Analyze Each Compound

1. **Propane (C3H8)**:
- Structure: CH3-CH2-CH3
- Analysis: This compound has three carbon atoms in a straight line with no side chains. Therefore, propane is a straight chain organic compound.

2. **Butane (C4H10)**:
- Structure: CH3-CH2-CH2-CH3
- Analysis: Butane consists of four carbon atoms arranged in a straight line without any side chains. Thus, butane is also a straight chain organic compound.

3. **Isobutene (C4H8)**:
- Structure: CH3-CH=CH-CH3
- Analysis: Isobutene is a branched compound. The presence of a double bond and the arrangement of carbon atoms indicate that there is a side chain. Therefore, isobutene is not a straight chain organic compound.

4. **Ethane (C2H6)**:
- Structure: CH3-CH3
- Analysis: Ethane has only two carbon atoms, and it cannot have any side chains. Thus, ethane is a straight chain organic compound.

### Conclusion
After analyzing all the compounds, the only compound that is not a straight chain organic compound is **isobutene**.

### Final Answer
**Isobutene** is the compound that is not a straight chain organic compound.

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