Final answer:
The empirical formula of caprylic acid is CH2O, and the molecular formula is C4H8O4.
Step-by-step explanation:
The empirical formula of caprylic acid can be determined by finding the ratio of the elements present. To do this, you need to convert the percentages of carbon, hydrogen, and oxygen into moles. Assuming we have 100g sample of caprylic acid, we can calculate the moles of each element. The moles of carbon would be 66.62% x 100g / atomic mass of carbon, the moles of hydrogen would be 11.2% x 100g / atomic mass of hydrogen, and the moles of oxygen would be (100% - (66.62% + 11.2%)) x 100g / atomic mass of oxygen. Once you have the moles, divide each mole value by the smallest mole value to get the simplest ratio. In this case, the simplest ratio is 1:4:2, which means the empirical formula of caprylic acid is CH2O.
The molecular formula of caprylic acid can be determined by comparing its molar mass to the molar mass of the empirical formula. In this case, the molar mass of the empirical formula CH2O is 30.02 g/mol. Since the molar mass of caprylic acid is given as 144.21 g/mol, we can calculate the integer n by dividing the molar mass of caprylic acid by the molar mass of the empirical formula: n = 144.21 g/mol / 30.02 g/mol = 4.8. We round this value to the nearest whole number and multiply the subscripts of the empirical formula (C1H2O1) by this integer. The molecular formula of caprylic acid is therefore C4H8O4.