Final answer:
The empirical formula of a compound with 14.4% hydrogen and 85.6% carbon by mass is CH2. This is found by converting percentages to moles, dividing by the smallest mole value, and simplifying to the smallest whole number ratio.
Step-by-step explanation:
To find the empirical formula of a compound with given mass percentages of its constituent elements, we must convert these percentages to moles, then simplify the ratios. In the case of a compound with 14.4% hydrogen and 85.6% carbon, we first assume a 100 g sample to bypass the conversion to grams. Doing so, we'd have 14.4 g of hydrogen and 85.6 g of carbon.
Since the atomic mass of hydrogen (H) is approximately 1 g/mol and that of carbon (C) is about 12 g/mol, we can now calculate the moles of each:
- Hydrogen: 14.4 g ÷ 1 g/mol = 14.4 moles
- Carbon: 85.6 g ÷ 12 g/mol = 7.13 moles
Next, we divide by the smallest number of moles to get the simplest whole number ratio:
- Hydrogen: 14.4 moles ÷ 7.13 moles ≈ 2
- Carbon: 7.13 moles ÷ 7.13 moles = 1
Therefore, the empirical formula of the compound is CH2.