17. Solving a chemistry problem

233. Through a column filled with a cation exchanger weighing 20 g, 3 ml of an aluminum sulfate solution were passed from a 250 ml volumetric flask. The flowing eluate with a volume of 100 ml, together with washing distilled water, was collected in a beaker and titrated potentiometrically with 0.056 N KOH solution. The titration took 4.5 ml of KOH solution. Determine the capacity of the cation exchanger for aluminum and the mass of anhydrous aluminum sulfate in the original flask.