Marble (calcium carbonate) reacts with hydrochloric acid solution to form calcium chloride solution, water, and carbon dioxide. what is the percent yield of carbon dioxide if 3.65 g of the gas is collected when 10.0 g of marble reacts?

CaCO3+2HCl→CaCl2+H2O+CO2
You have to find which is limiting first, we take 10g of marbles10g marbles×1 mol marbles/40+12+3(16)g marbles×1 mol CO2/1 mol marbles=0.4 mol CO2
Then0.4 mol CO2 ×12+2(16)g CO2/1 mol CO2=17.6g of CO2
Based on theoretical calculations, you should get 17.6g of CO2,  but it turns out that you only have 3.65g of CO2 collected, so,3.65g17.6g×100=20.7 percent

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