1. Calculate the mass of SO2 produced when 185 grams of oxygen reacts using this equation: 2Cu2S + 3O2 ----> 2Cu2O + 2SO2
2. If a student decomposes 58.498 grams of aluminum carbonate and she collects the gas and measures 27.68 grams of carbon dioxide, determine the percent yield for this reaction. Al2(CO3)3 ----> Al2O3 + 3CO2
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The reaction is: 2Cu2S + 3O2 ----> 2Cu2O + 2SO2
Molar mass of SO2 is (32+2*16) = 64.
From the stoichiometry of the above mentioned reaction,
3*2*16 = 96 g oxygen reacts with sufficient Cu2S to produce 2*64 = 128 g SO2.
Therefore, 185 g oxygen should react with sufficient Cu2S to produce 128*185/96 = 246.667 g SO2.
Therefore, 246.67 g SO2 will be produced when 185 g oxygen react with sufficient Cu2S.