Which among the following possesses an sp hybridized carbon in its structure ?

Options

A. `CH_(2)=C Cl -CH=CH_(2)`
B. `C.Cl_(2) =C. Cl_(2)`
C. `CH_(2)=C=CH_(2)`
D. `CH_(2) =CH-CH=CH_(2)`

Answer

To determine which of the given species possesses an sp hybridized carbon in its structure, we need to analyze the hybridization of carbon atoms in each option based on their bonding and steric number.

### Step-by-Step Solution:

1. **Understanding Hybridization**:
- The hybridization of a carbon atom can be determined by its steric number, which is the sum of the number of sigma bonds and lone pairs around the carbon atom.
- The hybridization types are as follows:
- **sp**: Steric number 2 (linear geometry)
- **sp2**: Steric number 3 (trigonal planar geometry)
- **sp3**: Steric number 4 (tetrahedral geometry)

2. **Analyzing Each Option**:
- **Option 1**:
- Structure: CH2=C(Cl)-CH2
- Carbon 1: 3 sigma bonds (2 from CH2 and 1 from C=Cl) → sp2 hybridized.
- Carbon 2: 3 sigma bonds (1 from C=Cl and 2 from CH2) → sp2 hybridized.
- Carbon 3: 3 sigma bonds (2 from CH2 and 1 from C=C) → sp2 hybridized.
- **Conclusion**: All carbons are sp2 hybridized. Not the correct option.

- **Option 2**:
- Structure: C(Cl)2=C=C(Cl)2
- Carbon 1: 3 sigma bonds (2 from Cl and 1 from C=C) → sp2 hybridized.
- Carbon 2: 3 sigma bonds (1 from C=C and 2 from Cl) → sp2 hybridized.
- Carbon 3: 3 sigma bonds (2 from Cl and 1 from C=C) → sp2 hybridized.
- **Conclusion**: All carbons are sp2 hybridized. Not the correct option.

- **Option 3**:
- Structure: CH2=C=C(H)2
- Carbon 1: 3 sigma bonds (2 from CH2 and 1 from C=C) → sp2 hybridized.
- Carbon 2: 2 sigma bonds (1 from C=C and 1 from C=H) → sp hybridized.
- Carbon 3: 3 sigma bonds (2 from H and 1 from C=C) → sp2 hybridized.
- **Conclusion**: One carbon is sp hybridized. This is a correct option.

- **Option 4**:
- Structure: CH2=CH-CH=CH2
- Carbon 1: 3 sigma bonds (2 from CH2 and 1 from C=C) → sp2 hybridized.
- Carbon 2: 3 sigma bonds (1 from C=C and 2 from CH) → sp2 hybridized.
- Carbon 3: 3 sigma bonds (1 from C=C and 2 from CH) → sp2 hybridized.
- Carbon 4: 3 sigma bonds (2 from CH2 and 1 from C=C) → sp2 hybridized.
- **Conclusion**: All carbons are sp2 hybridized. Not the correct option.

3. **Final Answer**:
- The only correct option that possesses an sp hybridized carbon in its structure is **Option 3** (CH2=C=C(H)2).