Final answer:
In the complete combustion that produces 33g of CO2 and 18g of H2O, we found there are 0.75 moles of carbon and 2 moles of hydrogen, leading to an empirical formula of C3H8 for the hydrocarbon.
Step-by-step explanation:
To determine the empirical formula of the hydrocarbon in a complete combustion that produces 33g of carbon dioxide (CO2) and 18g of water (H2O), we begin by finding the number of moles of carbon and hydrogen.
First, we know that the molar mass of CO2 is approximately 44 g/mol, which means that there are 33 g / 44 g/mol = 0.75 moles of CO2. This means there are 0.75 moles of carbon since each molecule of CO2 contains one carbon atom.
Next, water has a molar mass of approximately 18 g/mol. Hence, we have 18 g / 18 g/mol = 1 mole of H2O, which means 2 moles of hydrogen are present because each molecule of H2O contains two hydrogen atoms.
Therefore, the ratio of carbon to hydrogen atoms is 0.75 to 2, which simplifies to 3:8. This suggests that the empirical formula of the hydrocarbon is C3H8.