An electrogravimetric determination of iridium in ore is performed. The 0.2843 g sample of ore is processed to produce 110-mL solution of iridium(IV) as its soluble hexachloro ion, IrCl62-. The iridium is plated out from the solution onto a boron doped diamond electrode at constant potential. The initial mass of the electrode before plating was 7.4938 g, and the final mass was 7.4969 g.Calculate the mass percent of iridium in the ore assuming no other species was electroactive at the plating potential.