b
(b) We know that \(A{l^{ + 3}}\) cation is smaller than \(N{a^ + }\) (because of greater nuclear change) According to Fajan's rule, small cation polarise anion upto greater extent. Hence \(A{l^{3 + }}\) polarise \(C{l^ - }\) ion upto greater extent, therefore \(AlC{l_3}\) has covalent bond between \(Al\) and \(Cl\) atoms.