Shortest C-C bond length is present in

Options

A. `CH_3-CH_2-CH_3`
B. `CH_3CH_2CH_2CH_3`
C. `CH_2=CH-CH=CH_2`
D. `CH-=C-C-=CH`

Explanation

To determine which compound has the shortest C-C bond length, we can follow these steps:

### Step 1: Understand Bond Length and Bond Order
Bond length is inversely related to bond order. This means that as the bond order increases, the bond length decreases. The bond order for different types of carbon-carbon bonds is as follows:
- Single bond (C-C): Bond order = 1
- Double bond (C=C): Bond order = 2
- Triple bond (C≡C): Bond order = 3

### Step 2: Identify Hybridization and S-character
The hybridization of carbon atoms affects the bond length due to the percentage of s-character:
- **sp hybridization**: 50% s-character
- **sp2 hybridization**: 33% s-character
- **sp3 hybridization**: 25% s-character

As the s-character increases, the bond length decreases. Therefore, sp-hybridized carbon will have the shortest bond length.

### Step 3: Analyze the Options
Given the options, we need to identify the hybridization of the carbon atoms in each option:
1. Option 1: All single bonds (C-C)
2. Option 2: All single bonds (C-C)
3. Option 3: All sp2 hybridized carbon (C=C)
4. Option 4: All sp hybridized carbon (C≡C)

### Step 4: Compare the Bond Lengths
- In options 1 and 2, we have single bonds (C-C), which have the longest bond lengths.
- In option 3, we have double bonds (C=C), which have shorter bond lengths than single bonds but longer than triple bonds.
- In option 4, we have triple bonds (C≡C), which have the shortest bond lengths due to the highest bond order and the highest s-character.

### Conclusion
Based on the analysis, the shortest C-C bond length is present in **Option 4**, which contains sp hybridized carbon atoms.

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