Question

In which of the following molecule does the central atom have two p-orbitals unused?

Options

• BF₃

• BeF₂

• NH₃

• C₂H₂

Answer 1

BeF₂ 

Explanation:

Sp hybridization takes place with beryllium. Two ‘sp’ hybrid orbitals are created by the hybridization of one 2s and one 2p. There is no use for the other two 2p orbitals.

Sp²-hybridization takes place with BF₃. Only one p-orbital is still available. Since NH₃ experiences sp³-hybridization, all p orbitals are utilised. Sp hybridization occurs with acetylene (C₂H₂). Two pi bonds are created when the remaining two 2p orbitals of one carbon atom and the other overlap laterally.