In which of the following carbon is most electronegative?

Options

A. sp
B. `sp^(2)`
C. `sp^(3)`
D. Same in all

Explanation

To determine in which of the following forms carbon is most electronegative, we need to analyze the hybridization states of carbon and their corresponding S-character.

### Step-by-Step Solution:

1. **Understanding Electronegativity**: Electronegativity is the tendency of an atom to attract electrons towards itself when it is part of a compound. For carbon, its electronegativity can vary based on its hybridization state.

2. **Identifying Hybridization States**: Carbon can exist in different hybridization states:
- **sp Hybridization**: In this state, carbon forms two sigma bonds and has 50% S-character.
- **sp² Hybridization**: In this state, carbon forms three sigma bonds and has 33% S-character.
- **sp³ Hybridization**: In this state, carbon forms four sigma bonds and has 25% S-character.

3. **Relating S-character to Electronegativity**: The electronegativity of an atom is directly proportional to its S-character. This means that the more S-character an orbital has, the more electronegative the atom will be.

4. **Comparing S-character**:
- **sp (50% S-character)**: Highest electronegativity.
- **sp² (33% S-character)**: Moderate electronegativity.
- **sp³ (25% S-character)**: Lowest electronegativity.

5. **Conclusion**: Since sp hybridization has the highest S-character (50%), carbon in the sp hybridization state is the most electronegative.

### Final Answer:
The most electronegative form of carbon is in the **sp hybridization state**.