Question

Alkali metals reacts vigorously with halogens to form ionic halide M⁺ X^- however lithium halides are somewhat covalent.

Answer 1

Alkali metal halides are formed by the donation of valence electron from the metal to the halogen atom.Therefore, the halides are ionic.But lithium halides are somewhat covalent.This is due to the distortion of electron cloud of halide ion by the small lithium ion which induces covalent character in the lithium halides.