1-butyne and 1, 3-butadiene are :

Options

A. chain isomer
B. position isomer
C. functional isomer
D. tautomers

Answer

To determine the relationship between 1-butyne and 1,3-butadiene, we will analyze their structures, molecular formulas, and the type of isomerism they exhibit.

### Step 1: Identify the Structures
1. **1-butyne** has the structure:
- It has a carbon-carbon triple bond (C≡C) at the first position.
- The complete structure can be represented as CH≡C-CH2-CH3.

2. **1,3-butadiene** has the structure:
- It has two carbon-carbon double bonds (C=C) at the first and third positions.
- The complete structure can be represented as CH2=CH-CH=CH2.

### Step 2: Determine the Molecular Formula
- For **1-butyne**:
- The molecular formula is C4H6 (4 carbons and 6 hydrogens).

- For **1,3-butadiene**:
- The molecular formula is also C4H6 (4 carbons and 6 hydrogens).

### Step 3: Analyze the Type of Isomerism
- Both compounds have the same molecular formula (C4H6), indicating they are isomers.
- **Functional Isomers**:
- 1-butyne contains a triple bond (alkyne), while 1,3-butadiene contains double bonds (alkene).
- Since they differ in the type of functional groups (triple bond vs. double bond), they are classified as functional isomers.

### Conclusion
1-butyne and 1,3-butadiene are functional isomers because they have the same molecular formula but different functional groups.

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