According to Fajans'rules, the percentage of covalent character in an ionic compound increase if the cation is highly charged or small in size and the anion is large or cation has pseudoinert gas configuration. As a result of the increased covalent character, solubility in less polar solvent increases and the melting point decreases. The correct order of increasing ionic character is

Options

A. `NaCl lt KCl lt RbCl lt CsCl`
B. `NaCl lt KCl lt CsCl lt RbCl`
C. `KCl lt NaCl lt CsCl lt RbCl`
D. `CsCl lt RbCl lt KCl lt NaCl`

Answer

A

Explanation

As the size of the cation increases, the electronegativity decreases and the electronegativity difference increases and henceionic character increases.