Final answer:
The empirical formula represents the simplest whole-number ratio of elements in a compound. It's crucial for determining the basic composition of a compound in chemistry. Acetic acid's empirical formula, for example, is CH2O, reflecting a simplified ratio of its constituent atoms.
Step-by-step explanation:
The term "empirical formula" refers to a simple expression representing the simplest whole-number ratio of the elements in a compound. It does not show the actual number of atoms of each element, but rather the lowest ratio in which the elements combine to form the compound. For instance, glucose has a molecular formula of C6H12O6, but its empirical formula is CH2O because the subscripts in the molecular formula can be divided by six, giving the lowest ratio of 1:2:1. This process of determining the empirical formula often involves converting the mass of each element in a compound to moles and subsequently finding the smallest whole-number ratios of these moles.
An interesting example is acetic acid, where its molecular formula is C2H4O2. When we divide the subscripts by the lowest common denominator (2), we get an empirical formula of CH2O, indicating a 1:2:1 ratio for carbon, hydrogen, and oxygen, respectively. Determining the empirical formula is a fundamental step in analyzing the composition of an unknown compound in chemistry.