Molecular and Empirical Forumlas from Percent Composition

This paragraph introduces the process of determining the empirical and molecular formulas for eugenol, a compound with a molar mass of 164.2 grams per mole. It explains the composition of eugenol, which is 73.14% carbon, 7.37% hydrogen, and the remainder being oxygen. The paragraph emphasizes the difference between empirical and molecular formulas, with the former being the simplest ratio of atoms and the latter representing the actual count. It begins the calculation by using the molar mass and composition percentages to find the mass of each element in eugenol, leading to the calculation of moles of carbon, hydrogen, and oxygen present in one mole of eugenol.

This section delves into the specifics of calculating the moles of carbon, hydrogen, and oxygen in eugenol using their respective atomic weights. It provides a refresher on the atomic weights of these elements: carbon at approximately 12 grams per mole, hydrogen at 1 gram per mole, and oxygen at 16 grams per mole. The paragraph guides through the calculation of moles for each element based on the mass found in the previous section, resulting in 10 moles of carbon, 12 moles of hydrogen, and 2 moles of oxygen in one mole of eugenol. It then explains how to derive the molecular formula from these moles and simplifies the ratio to find the empirical formula.

The final paragraph focuses on simplifying the ratio of atoms obtained from the molecular formula to arrive at the empirical formula. It points out that the numbers of moles of carbon, hydrogen, and oxygen have a common factor of 2, which can be divided to get the simplest form. The result is an empirical formula of C5H6O for eugenol, which represents the simplest whole number ratio of atoms in the compound. The paragraph ensures that the distinction between the molecular and empirical formulas is clear and that the process of simplification is correctly applied.