1. An iron ore sample weighing 0.9132 g is dissolved in HCl (aq), and the iron is obtained as Fe²⁺ (aq). This solution is then titrated with 28.72 mL of 0,05051 M K₂Cr₂O₇. What is the mass percent Fe in the ore sample? (30 points)

Fe²⁺ (aq) + Cr₂O₇^2- (aq)-->Fe³⁺ (aq)+ Cr³⁺ (aq)