Among the following compounds, which one has the shortest `C-Cl` bond?

Options

A. `H_(3)C-Cl`
B.
C.
D.

Answer

To determine which compound has the shortest C-Cl bond among the given options, we need to analyze the nature of the bonds in each compound. Here's a step-by-step solution:

### Step 1: Identify the Compounds
First, we need to identify the compounds provided in the question. Let's assume the compounds are:
1. CH3Cl (Methyl chloride)
2. CH2=CHCl (Vinyl chloride)
3. C6H5Cl (Chlorobenzene)
4. CHCl3 (Chloroform)

### Step 2: Analyze the Bond Types
Next, we analyze the type of bonds present in each compound:
- **CH3Cl**: Contains a single C-Cl bond.
- **CH2=CHCl**: Contains a C-Cl bond, but the carbon is involved in a double bond with another carbon (C=C).
- **C6H5Cl**: The C-Cl bond is attached to a carbon in a benzene ring, which has resonance.
- **CHCl3**: Contains a single C-Cl bond.

### Step 3: Consider Bond Length Trends
In general, the bond length decreases with increasing bond order:
- Single bonds (C-Cl) are longer than double bonds (C=C) and triple bonds (C≡C).
- However, resonance and hybridization can affect bond lengths as well.

### Step 4: Evaluate the Compounds
1. **CH3Cl**: The C-Cl bond length is relatively long due to the single bond.
2. **CH2=CHCl**: The C-Cl bond may have some double bond character due to the adjacent double bond, which can shorten the bond length.
3. **C6H5Cl**: The C-Cl bond is affected by resonance in the benzene ring, which can also lead to a shorter bond length compared to a simple single bond.
4. **CHCl3**: Similar to CH3Cl, the C-Cl bond is a single bond and relatively long.

### Step 5: Conclusion
Among these compounds, **CH2=CHCl (Vinyl chloride)** is expected to have the shortest C-Cl bond due to the presence of the adjacent double bond, which imparts some double bond character to the C-Cl bond.

### Final Answer
**The compound with the shortest C-Cl bond is CH2=CHCl (Vinyl chloride).**

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