Final answer:
To determine the empirical formula of a hydrocarbon, calculate the moles of carbon and hydrogen from the masses of CO2 and H2O produced during combustion, and then express these moles in the simplest whole number ratio.
Step-by-step explanation:
To find the empirical formula of a hydrocarbon that has been combusted, we start by calculating the moles of carbon and hydrogen from the mass of carbon dioxide (CO2) and water (H2O) produced.
Using the molar mass of carbon dioxide (44.01 g/mol), the moles of carbon in 23.118 g of CO2 are calculated. Similarly, using the molar mass of water (18.02 g/mol), the moles of hydrogen in 4.729 g of H2O are found.
Once the moles of carbon and hydrogen are determined, we express these amounts as the simplest whole number ratio to find the empirical formula of the hydrocarbon. If the amounts are not whole numbers, they are normally multiplied by a small integer to achieve whole numbers.
The combustion of hydrocarbons always yields CO2 and H2O. Therefore, by calculating the moles of carbon from the CO2 produced and the moles of hydrogen from the H2O produced, the empirical formula can be inferred.