45. Solving a chemistry problem

Manganese in the sample was determined by the complexometric method. To do this, a sample weighing 1.0000 g was dissolved and transferred into a volumetric flask with a capacity of 200.0 cm3. For titration of 20.0 cm3 of the resulting solution, 10.0 cm3 of a 0.0500 mol/dm3 solution of complexone III was used. Calculate the mass fraction of manganese in the sample. Write down the equation for the ongoing reaction.