EDTA和钙离子1:1络合.
取碳酸钙物质的量=(0.1005*25/100)/100=0.00025125mol.
EDTA的浓度=0.00025125mol/0.0249L=0.01009mol/L.
EDTA和Zn和Fe均1:1络合.
1mLEDTA相当于0.01009×10^-3molZnO和0.5×0.01009×10^-3molFe2O3.
ZnO的质量为0.01009×10^-3mol*81.04g/mol=0.817mg.
Fe2O3的质量为0.5×0.01009×10^-3mol*159.7g/mol=0.8057mg.