The number of sp² hybrid orbitals in a molecule of benzene is :

Solution

Chemistry ma’am · 3 steps

Every carbon in benzene mixes three orbitals into sp², so count 6 carbons times 3 orbitals each.

1. Hybridisation of carbon. Each carbon in C₆H₆ forms three σ bonds: two to neighbouring carbons and one to a hydrogen. Three σ bonds and no lone pair means each carbon is sp² hybridised.
2. Orbitals per carbon. Mixing one s and two p orbitals gives three sp² hybrid orbitals on each carbon. The fourth orbital, an unhybridised p orbital, forms the π system and is not counted.

   6 carbons × 3 sp² orbitals each = 18

3. So. Benzene has 18 sp² hybrid orbitals, which is option (d).

The idea to keep. Count hybrid orbitals as (number of hybridised atoms) times (orbitals per atom): sp gives 2, sp² gives 3, sp³ gives 4. Hydrogen uses its plain 1s orbital.

Answer from the NTA final answer key. Solution by PrepWiser.