Aluminum ions determined by titrating with EDTA:
Al^3+^ + H_2_Y^2-^ >>> AlY^-^ + 2H^+^
1.00 g sample requires 20.5 ml EDTA for titration. the EDTA was standardized by titrating 25.0 mL of a 0.1 M CaCl2 solution, requiring 30.0mL EDTA. Calculate the percent Al2O3 in the sample. I want also to know how we can deduce the relation between Al and EDTA, AL2O3 and EDTA? And why the three Oxygen molecules are not involved in the reaction written above?
Thank you in advance.