Calculations for determining the mass percent of Mg2+ in the unknown. Calculations for determining the concentration of Mg2+ at specified points before and after the equivalence point. Data Set \#5 - Concentration of EDTA =0.01021M - 5.22g of unknown containing Mg2+ - 250mL Volumetric Flask - 25mL pipette - Aliquot of magnesium solution is placed in a 250mL Erlenmeyer flask. 20.0mL of distilled water and 10.00mL of pH10.00 buffer is added. - Volume of EDTA before equivalence (10.00mL) - Volume of EDTA after the equivalence (25.00ml)