Question

The reaction below shows the combustion of butane (C4H10). Why is the mole ratio (8 moles CO2/2 mol C4H10) used to determine the amount of carbon dioxide (CO2) produced when butane (C4H10) combusts in excess oxygen?

C4H10 + O2 yields CO2 + H2O + heat
A: Butane has a mass that is 4 times greater than CO2, so only 2 moles of C4H10 are needed to produce 8 moles of CO2.
B: Carbon dioxide has a volume of about one-quarter that of C4H10, so 4 moles of CO2 are needed to react with each mole of C4H10.
C: During combustion, CO2 is approximately 4 times more reactive than C4H10, so less C4H10 will participate in the reaction.
D: When the chemical equation for butane combustion is balanced, 2 moles of C4H10 are needed to produce 8 moles of CO2.

Answer 1

The mole ratio (8 moles CO2/2 mol C4H10) is based on the balanced chemical equation for the combustion of butane, indicating that 2 moles of butane produce 8 moles of carbon dioxide.

Step-by-step explanation:

The correct answer to the question of why the mole ratio (8 moles CO2/2 mol C4H10) is used to determine the amount of carbon dioxide (CO2) produced when butane (C4H10) combusts in excess oxygen is option D: When the chemical equation for butane combustion is balanced, 2 moles of C4H10 are needed to produce 8 moles of CO2. The balanced chemical equation for the complete combustion of butane is 2C4H10 + 13O2 → 8CO2 + 10H2O. Once balanced, it is clear that every 2 moles of butane will produce 8 moles of carbon dioxide.

The number of moles of products in a chemical reaction can be determined using the balanced equation, which provides the mole ratios of reactants to products. This is crucial for stoichiometric calculations in combustion reactions and other chemical processes.