A language is a system of communication, consisting of a set of sounds or written symbols that enable people to communicate. In chemistry, a particular language is required in order to represent the phenomenological world by means of symbols. Choosing the right words and knowing the precise definitions for chemical concepts is needed for avoiding misconceptions. Despite the creation of International Union of Pure and Applied Chemistry (IUPAC), fundamental notions are still undergoing constant debate, in particular concerning the conceptual distinction between element, atom, molecule, compound, chemical species and substance. In this article, we propose to better distinguish categories of chemical objects and their element, and to define a molecule as a stable and electrically neutral chemical entity that exists with a finite number of chemical bonds (0 to "n," with "n" finite number). This new definition implies that "noble gases," i.e., reduced to one isolated atom, are made of molecules, that all bonded atoms are atoms, and enables distinguishing both of these from "compounds." We insist that chemical education makes a clear difference between objects and categories, emphasizing the importance of understanding that elements and compounds represent categories of nuclei, whereas chemical entities and substances are a sample of matter. We also point out a number of nuances in chemical language, primarily in order to avoid misconceptions regarding the macroscopic physical properties relating to chemical substances and chemical objects.