Question

Which are Lewis Acids and which are Lewis Bases?

CO³⁺

BCl₃

OF₂

Cl^-

CO₂

Answer 1

Lewis acid: A Lewis acid is any species that can accept a pair of electrons for example AlCl₃ which can accept lone pair of electron. All cations are Lewis acids since they are able to accept electrons.

CO3+ , BCl3 (boron very readily accepts electrons from other molecules, which is why it generally behaves as a Lewis acid), CO2 (after cleaving one pi bond from CO2 there is a positive charge over carbon atom and negative charge on oxygen atom, the positive charge makes it Lewis acid)

Lewis base: A Lewis base is a species that can donate a pair of electrons to an electron acceptor for example OH- which can donate electron pair to Lewis acid H+ to form H2O.

Cl- (presence of negative charge) and OF2 (has lone pair of eklectrons to share with other electron defficient species.)