What are electron deficient compounds

Explanation:

The species, which have less than 8 electrons in the valence shell or the species, which have 8 valence electrons, but has empty orbitals, so that the covalency can be spread beyond 4, are called as electron deficient species.BCI₃ is electron deficient compound because boron has only 6 valence electron and is short of 2 electrons.Therefore it can accept a pair of electrons from nucleophiles.SiC1₄ is not electron deficient compound because silicon has 8 valence electrons. It cannot spread its covalency beyond 4 because silicon doesn’t have d- orbitals.

Final Answer:

The species, which have less than 8 electrons in the valence shell or the species, which have 8 valence electrons, but has empty orbitals, so that the covalency can be spread beyond 4, are called as electron deficient species.BCI₃ is electron deficient compound because boron has only 6 valence electron and is short of 2 electrons.Therefore it can accept a pair of electrons from nucleophiles.SiC1₄ is not electron deficient compound because silicon has 8 valence electrons. It cannot spread its covalency beyond 4 because silicon doesn’t have d- orbitals.