The hybridisation of carbon atoms in C - C single bond is `HC-=C-CH=CH_(2)` is

Options

A. `Sp^(3)-Sp^(3)`
B. `Sp^(2)-Sp^(3)`
C. `Sp-Sp^(2)`
D. `Sp^(3)-Sp`

Answer

To determine the hybridization of the carbon atoms in the compound HC≡C-CH=CH₂, we will analyze the structure step by step.

### Step 1: Identify the structure
The compound HC≡C-CH=CH₂ can be broken down as follows:
- The first carbon (C1) is connected to a hydrogen (H) and has a triple bond with the second carbon (C2).
- The second carbon (C2) is connected to the first carbon (C1) via a triple bond and to the third carbon (C3) via a single bond.
- The third carbon (C3) is connected to the second carbon (C2) via a single bond and has a double bond with the fourth carbon (C4).
- The fourth carbon (C4) is connected to the third carbon (C3) via a double bond and has two hydrogen atoms attached to it.

### Step 2: Analyze the hybridization of each carbon
1. **Carbon C1 (HC≡C)**:
- C1 has 4 valence electrons.
- It forms a triple bond with C2 (which consists of 1 sigma bond and 2 pi bonds) and has 1 hydrogen atom attached.
- The steric number for C1 is 1 (from the sigma bond with C2) + 0 (lone pairs) = 1.
- Therefore, the hybridization of C1 is **sp**.

2. **Carbon C2 (C≡C-CH)**:
- C2 also has 4 valence electrons.
- It forms a triple bond with C1 (1 sigma bond, 2 pi bonds) and a single bond with C3.
- The steric number for C2 is 1 (from the sigma bond with C1) + 1 (from the single bond with C3) + 0 (lone pairs) = 2.
- Therefore, the hybridization of C2 is **sp**.

3. **Carbon C3 (CH=CH₂)**:
- C3 has 4 valence electrons.
- It forms a single bond with C2 and a double bond with C4 (which consists of 1 sigma bond and 1 pi bond).
- The steric number for C3 is 1 (from the single bond with C2) + 1 (from the double bond with C4) + 0 (lone pairs) = 2.
- Therefore, the hybridization of C3 is **sp²**.

4. **Carbon C4 (CH₂)**:
- C4 has 4 valence electrons.
- It forms a double bond with C3 and has 2 hydrogen atoms attached.
- The steric number for C4 is 1 (from the double bond with C3) + 2 (from the two hydrogen atoms) + 0 (lone pairs) = 3.
- Therefore, the hybridization of C4 is **sp²**.

### Conclusion
- C1: sp hybridization
- C2: sp hybridization
- C3: sp² hybridization
- C4: sp² hybridization

### Final Answer
The hybridization of the carbon atoms in HC≡C-CH=CH₂ is:
- C1: sp
- C2: sp
- C3: sp²
- C4: sp²