What represents a chemical formula?

A chemical formula specifically represents the elemental composition of a molecule, indicating which elements are present and in what proportions. For example, the molecular formula for water is H2O, which tells you that there are two hydrogen atoms and one oxygen atom in each molecule of water. This type of formula is crucial for understanding the basic composition of substances in biochemistry.

In contrast, other options refer to different aspects of molecular representation. While some may display structures or connectivity, a chemical formula is focused solely on the types and quantities of atoms in a compound. Thus, it lacks information about the spatial arrangement or three-dimensional shape of the molecule, making the choice that emphasizes elemental composition the best representation of a chemical formula.