👉 The term "transempirical" is a concept in chemistry that refers to a chemical reaction that involves two or more reactants, and one of them is an empirical formula (i.e., it can be calculated from known values), while the other is not. This kind of reaction is called transempirical because it can only occur when both reactants are assumed to have the same number of atoms. For example, consider a chemical reaction that involves the following two reactants: 1.