What does a molecular formula indicate?

A molecular formula provides essential information about the composition of a molecule by indicating the number of atoms of each element present. This formula typically consists of the symbols for the elements followed by subscripts that denote how many atoms of each element are present in a single molecule of the compound. For example, in water (H2O), the molecular formula indicates that there are two hydrogen atoms and one oxygen atom in each molecule.

The other options do not accurately describe what a molecular formula conveys. While ratios of molecules in a reaction might be represented in a balanced chemical equation, this is distinct from a molecular formula. Similarly, the order of elements in a compound is not indicated by a molecular formula; instead, this information might be represented by a structural formula. Lastly, the types of chemical bonds present (like ionic or covalent) are also not discernible solely from the molecular formula. Thus, the correct answer highlights the primary function of a molecular formula, which is to specify the exact number of atoms of each element contained within a molecule.