2. Solving a chemistry problem

12. A sample of steel weighing 1.43 g was dissolved, iron was oxidized to Fe (II) and titrated potentiometrically with a solution of potassium permanganate. The following data were obtained: С(1/5 KMnO4)=0.001046 mol/l.
V(KMnO4), ml 5.00 10.00 15.00 19.00 19.50 20.00 20.50 21.00 23.00
E, mV 713 774 805 840 886 1107 1345 1370 1395
Build a titration curve, find the potential and volume of potassium permanganate at the equivalence point, calculate the mass fraction of iron in the analyzed sample.