The correct order of melting points for the following calcium halides is: — Chemical Bonding Chemistry Question

💡 Solution & Explanation

Melting point generally decreases as covalent character increases. By Fajan's rule, covalent character increases with larger anion size ($F^- < Cl^- < Br^- < I^-$). Since $CaI_2$ has the most covalent character, it has the lowest melting point, while the highly ionic $CaF_2$ has the highest melting point.