24. Solving a chemistry problem

3. Coagulation of the negative sol of arsenic (III) sulfide is caused by the electrolytes KNO3, MgCl2 and AlCl3, for which the coagulation thresholds are respectively equal to 50.0; 0.72; 0.093 mmol/l. How do the coagulating abilities of the cations of the electrolytes considered relate to each other?