Final answer:
The empirical formula for a compound with 52.2% carbon, 13.0% hydrogen, and 34.8% oxygen by mass is C2H6O, determined by converting mass percentages to moles and finding the simplest whole number ratio.
Step-by-step explanation:
To determine the empirical formula of a compound containing C, H, and O, such as the one described with 52.2% carbon, 13.0% hydrogen, and 34.8% oxygen, one would first assume a 100 g sample. This makes it straightforward to convert percentages to grams. You would then convert the mass of each element to moles by dividing the mass by its atomic weight (C: 12.01 g/mol, H: 1.008 g/mol, O: 16.00 g/mol).
Calculating the number of moles:
- C: 52.2 g / 12.01 g/mol = 4.346 moles
- H: 13.0 g / 1.008 g/mol = 12.897 moles
- O: 34.8 g / 16.00 g/mol = 2.175 moles
Next, you identify the smallest number of moles and divide all mole quantities by that number to get the simplest whole number ratio:
- C: 4.346 / 2.175 = 2
- H: 12.897 / 2.175 = 6
- O: 2.175 / 2.175 = 1
The empirical formula derived from these ratios is C2H6O.