Among the following the maximum covalent character is shown by the compound

Options

A. `FeCl_2`
B. `SnCl_2`
C. `AlCl_3`
D. `MgCl_2`

Answer

C

Explanation

Covalent character is favoured by Fajan’s rule.
(i) Larger the charge on the ions.
(ii) Smaller the size of cations.
(iii) Larger the size of anions.
(iv) Cation with 18-electron structure (e.g., `Cu^+`), then larger polarising power and the covalent character is favoured. In all the given compounds, anion is same (`Cl^–`), hence polarising power is decided by size and charge of cation. Al3+ with maximum charge and smallest size has maximum polarising power hence, `AlCl_3` is maximum covalent.