9. Solving a chemistry problem

5. Determine the molar concentration of the equivalent of a sulfuric acid solution if an excess of BaCl2 is added to 10.00 ml of H2SO4 solution. The precipitate is filtered off, washed. 50.00 ml of a 0.05000 M solution of complexone III was added to the precipitate, the excess of the latter was titrated with 20.50 ml of a 0.04500 M solution of MgSO4.