Question

A solution is made by dissolving 28.8 grams of aluminum chloride, AlCl_3, in enough water to make exactly 100 mL of solution. what is the concentration (molarity) of the following in mol/L? [AlCl_3=2.161M] (Al^3+=__M), [Cl^-=__M]**(i was able to calculate the molarity for the whole solution but how do you do the individual Al^3+ and Cl^-**