Which hybrid orbitals are used by carbon atoms in the following molecules?
CH₃ – CH₃
Both carbon atoms use sp³ hybrid orbitals.
CH₃ – CH = CH₂
The CH₃ carbon uses sp³ hybrid orbitals, while the other two carbons use sp² hybrid orbitals.
CH₃ – CH₂ – OH
Both carbon atoms use sp³ hybrid orbitals.
CH₃ – CHO
The CH₃ carbon uses sp³ hybrid orbitals, while the CHO carbon uses sp² hybrid orbitals.
CH₃COOH
The CH₃ carbon uses sp³ hybrid orbitals, while the COOH carbon uses sp² hybrid orbitals.
Explanation
The hybridisation of a carbon atom depends on the type of bonds it forms. Carbon atoms forming only single bonds (like in ethane) undergo sp³ hybridisation. Carbon atoms involved in double bonds (like in ethene) undergo sp² hybridisation. Applying this principle to the given molecules: (a) Ethane has both carbons in sp³ state. (b) Propene has one sp³ carbon and two sp² carbons. (c) Ethanol has both carbons in sp³ state. (d) Ethanal has one sp³ carbon and one sp² carbon. (e) Ethanoic acid has one sp³ carbon and one sp² carbon.