Pyrite is a mineral with formula FeS2. An impure sample of pyrite, known to be 90-95% w/w FeS2, is to be analyzed by oxidizing all the sulfur to SO4 2-, and then precipitating as BaSO4. Exactly how many grams of the sample must be taken if a minimum of 1.0 gram of BaSO4 is desired? ( stoichiometry)