Brutoformule

Brutoformule, a term used in chemistry, refers to the actual number of each type of atom present in a molecule or formula unit of a compound. It conveys the exact composition in terms of elemental counts, independent of how the atoms are arranged. The term is used in several languages, including Dutch, Danish, and Norwegian, to describe the overall, unreconstrued composition of a substance.

In practical use, the brutoformule often corresponds to the molecular formula of a compound. For discrete molecules, the brutoformule equals the molecular formula, such as H2O for water or C6H12O6 for glucose. For some substances, especially ionic compounds like NaCl, the formula unit NaCl serves as the brutoformule, reflecting the simplest whole-number ratio of the ions in the substance. The brutoformule does not, by itself, indicate how atoms are bonded or arranged in space.

The brutoformule is distinct from the empirical formula, which shows only the simplest whole-number ratio of elements in a compound. For example, glucose has a molecular formula C6H12O6 and an empirical formula CH2O, whereas benzene has both a molecular (C6H6) and an empirical formula CH, which happen to be the same in this case. The empirical formula provides ratio information, while the brutoformule/molecular formula provides the actual counts in a single molecule.

Because the brutoformule does not describe connectivity or structure, it is often complemented by structural or condensed structural formulas when a full representation of the compound’s arrangement is needed.