Final answer:
To find the empirical formula of a compound from the percent composition, convert the percentages to moles using atomic masses, then determine the smallest mole ratio for each element and use this to deduce the empirical formula. The given percentages of carbon and hydrogen need to be converted into moles, with the remaining percentage assumed to be oxygen.
Step-by-step explanation:
To determine the empirical formula of a compound, you first assume a 100 g sample which makes the percent composition equal to the mass of each element in grams. With 54.53% carbon and 9.15% hydrogen, we perform the following steps:
- Convert the percentages to moles by dividing by the atomic mass of each element (12.01 g/mol for C and 1.008 g/mol for H).
- This results in 4.54 moles of C and 9.08 moles of H.
- Determine the smallest mole ratio by dividing the moles of each element by the smallest number of moles calculated.
- The resulting mole ratio of C to H is approximately 1:2.
The oxygen percentage is not directly given but can be determined by subtracting the sum of the carbon and hydrogen percentages from 100%.
- With the missing mass attributed to oxygen, calculate the moles of oxygen in the same manner.
The compound's empirical formula is based on these calculated mole ratios.