The correct order is, II > III > IV > I Identify the counter-ions in each electrolyte KCl:Cl−,K4[Fe(CN)6]:[Fe(CN)6]4−, K3PO4:PO43−,K2SO4:SO42− Charge −1,−4,−3,−2 Now applying Hardy-Schulze rule The higher the charge of counter ions, the greater is precepitals power Fe(CN6)4−>PO43−>SO42−>Cl−