Pentane, which has the chemical formula C5H12, reacts with oxygen to produce carbon dioxide and water according to the following balanced chemical equation:
2 C5H12 + 25 O2 -> 10 CO2 + 12 H2O
To determine the mass of carbon dioxide produced when 18.7 grams of pentane is burned, we can use the stoichiometry of the chemical reaction. Stoichiometry is the study of the quantities of reactants and products in a chemical reaction, and it allows us to predict the amount of a product that will be produced based on the amount of reactant consumed.
Since the chemical equation is balanced, we know that for every 2 molecules of pentane that react, 10 molecules of carbon dioxide are produced. This means that for every 2 grams of pentane that react, 10 grams of carbon dioxide will be produced.
Since 18.7 grams of pentane is equivalent to 18.7 / 2 = 9.35 moles of pentane, we can use this value to calculate the number of moles of carbon dioxide produced:
9.35 moles of pentane * (10 moles of CO2 / 2 moles of C5H12) = 9.35 * 5 = 46.75 moles of CO2
To convert the number of moles of carbon dioxide to mass, we can use the molar mass of carbon dioxide, which is 44.01 grams per mole:
46.75 moles of CO2 * 44.01 grams/mole = 2068.7 grams of CO2
Therefore, if 18.7 grams of pentane is burned, approximately 2068.7 grams of carbon dioxide is produced.