What is an empirical formula?

An empirical formula represents the simplest whole-number ratio of the different types of atoms present in a compound. It provides valuable information about the relative proportions of elements within a substance but does not convey the actual number of atoms in a molecule. For instance, the empirical formula for glucose is CH₂O, which signifies that for every carbon atom, there are two hydrogen atoms and one oxygen atom, reflecting the basic composition without highlighting the total number of atoms in a complete molecule of glucose (C₆H₁₂O₆).

This distinguishing feature is critical in chemistry, as empirical formulas help chemists understand the overarching composition of substances while allowing for a straightforward comparison of different compounds. The other options do not correctly define the empirical formula, as they pertain to the molecular formula, molecular weight, or structural representations, which encompass more detail than what is provided by an empirical formula.