Iron pyrite (Fes,) reacts with oxygen according to the following equation: 4FES,+ 110, 2Fe,0, + 8SO, If 250 g of Fes, is burned in 200 g of 0,, 100 grams of Fe,0, is produced. What is the percent yield of Fe,0,? (Molar mass for Fes, = 119.99g/mol, O = 16.00g/mol, Fe,O, = 159.70 g) Select one: a. 72% b. 52% c. 60% d. 86%

4.47 Silicon carbide is, an abrasive used in the manufacture of grinding wheels. A company is investigating whether they can be more efficient in the construction of such wheels by making their own SiC via the reaction SiO2+3CSiC+2CO (a) If this reaction consistently has a yield of 85%, what is the minimum amount of both silicon dioxide and carbon needed to produce 3400 kg of SiC for the manufacture of cutting wheels? (b) The silicon dioxide is to he obtained from sand and the carbon is derived from coal. If the available sand is 95% SiO2 by weight and the coal is 73% C by weight, what mass of coal is needed for each metric ton of sand used?

4.17 Phosgene is a highly toxic gas that has been used as a chemical weapon at times in the past. It is now used in the manufacture of polycarbonates, which are used to make phone cases and plastic eyeglass lenses. Phosgene is produced by the reaction, CO+Cl2COCl2 . Given an excess of carbon monoxide, what mass of chlorine gas must be reacted to form 4.5 g of phosgene?

Write the balanced chemical equation for the complete combustion of adipic acid, an organic acid containing 49.31% C, 6.90% H, and the remainder O, by mass.