Question

$B{H}_3$ is a lewis acid because :

• A. it has empty d-orbitals to accept lone pair of electrons
• B. it has empty p-orbitals to accept lone pair of electrons
• C. it has $2p$ electrons to donate
• D. none of these

Answer 1

The correct option is B it has empty p-orbitals to accept lone pair of electrons

Lewis acid is a chemical species that reacts with a Lewis base to form a Lewis adduct. In Borane, boron has only six valence electrons. It is therefore electron deficient and has empty p-orbitals. Hence, it can accept a lone pair.