Arrange the following in the increasing order of their covalent character. CaF ₂ ; CaCl ₂ ; CaBr ₂ ; CaI ₂

Step-by-step solution

According to Fajan's rule, the covalent character in ionic compounds increases with the increase in the polarizability of the anion. The polarizability of an anion depends on its size; larger anions are more easily polarized by the cation. The cations in all the given compounds are the same, which is Ca ²⁺ . The anions are F ⁻ , Cl ⁻ , Br ⁻ , and I ⁻ . The size of the halide ions increases in the order: F ⁻ Since the polarizability increases as the size of the anion increases, the covalent character follows the ord