An iron ore sample weighing 0.9292g is dissolved in HCl(aq), and the iron is obtained as Fe2+(aq). This solution is then titrated with 30.86mL of 5.027×10−2M K2Cr2O7(aq).
6Fe2++14H++Cr2O2−7→6Fe3++2Cr3++7H2O
So how would i go about finding the mass percent of Fe in the ore sample...