Question

Which is the correct increasing order of covalent character?

• A. $\mathrm{KCl}<{\mathrm{CaCl}}_2<{\mathrm{AlCl}}_3<{\mathrm{SiCl}}_4$
• B. ${\mathrm{AlCl}}_3<{\mathrm{CaCl}}_2<\mathrm{KCl}<{\mathrm{SiCl}}_4$
• C. None of these

Answer 1

The correct option is A

$\mathrm{KCl}<{\mathrm{CaCl}}_2<{\mathrm{AlCl}}_3<{\mathrm{SiCl}}_4$

The correct option is (a).

An explanation of the correct answer:

1. The covalent character of ionic compounds is governed by Fajan's rule.
2. The high positive charge cation (${\mathrm{SiCl}}_4$) has a greater covalent character.
3. High polarization with a smaller size cation and larger size anion has a maximum covalent character.
4. So, the option is correct.

The explanation of the incorrect answer:

Option (B):

1. The positive ion charge of Aluminium is denser than Calcium and Potassium.
2. So, the option is incorrect.