Calamine lotion contains a mixture of both zinc and iron oxides. A 1.022 g sample of dried calamine was dissolved in acid and diluted to 100.00 mL. Potassium fluoride (MW = 58.10 g/mol) was added to the solution to mask the iron. The pH was then adjusted and the solution was titrated with 0.1294 M EDTA. The solution required 77.42 mL to reach the equivalence point. Determine the percent ZnO (MW = 81.39 g/mol) in the sample.