All the carbon atoms in benzene are ....... hybridised.

Answer

To determine the hybridization of carbon atoms in benzene, we can follow these steps:

### Step 1: Understand the Structure of Benzene
Benzene is a cyclic compound consisting of six carbon atoms arranged in a ring. Each carbon atom is bonded to one hydrogen atom, resulting in a molecular formula of C6H6. The structure features alternating single and double bonds, which can be represented as a resonance hybrid.

**Hint:** Remember that benzene has a unique structure with alternating bonds, which contributes to its stability.

### Step 2: Identify the Type of Bonds
In benzene, each carbon atom forms three sigma (σ) bonds: two with neighboring carbon atoms and one with a hydrogen atom. Additionally, there is one pi (π) bond formed by the overlap of p orbitals between adjacent carbon atoms.

**Hint:** Count the number of sigma and pi bonds to understand the bonding in benzene.

### Step 3: Calculate the Steric Number
The steric number is calculated as follows:
- Count the number of sigma bonds.
- Add the number of lone pairs (which is zero in the case of benzene).
- Add any negative charges (also zero here).

For each carbon in benzene:
- Number of sigma bonds = 3 (two with adjacent carbons and one with hydrogen)
- Lone pairs = 0
- Negative charges = 0

Thus, the steric number for each carbon atom is:
\[ \text{Steric Number} = 3 + 0 + 0 = 3 \]

**Hint:** The steric number helps determine the hybridization of the atom.

### Step 4: Determine the Hybridization
Based on the steric number:
- A steric number of 2 corresponds to sp hybridization.
- A steric number of 3 corresponds to sp² hybridization.
- A steric number of 4 corresponds to sp³ hybridization.

Since the steric number for each carbon in benzene is 3, the hybridization is sp².

**Hint:** Use the steric number to find the corresponding hybridization type.

### Step 5: Conclusion
All carbon atoms in benzene are sp² hybridized.

**Final Answer:** All the carbon atoms in benzene are sp² hybridized.

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