Stoichiometric names of elements and binary compounds

The stoichiometric name of the compound is then formed by combining the name of the electropositive constituent, cited first, with that of the electronegative constituent, both suitably qualified by any necessary multiplicative prefixes ( mono , di , tri , tetra , penta , etc., given in Table IV). The multiplicative prefixes precede the names they multiply, and are joined directly to them without spaces or hyphens. The final vowels of multiplicative prefixes should not be elided (although monoxide , rather than monooxide , is an allowed exception because of general usage). The two parts of the name are separated by a space in English. 

Stoichiometric names may correspond to the empirical formula or to a molecular formula different from the empirical formula (compare Examples 3 and 4 below). 

Multiplicative prefixes need not be used in binary names if there is no ambiguity about the stoichiometry of the compound (such as in Example 10 above). The prefix mono is, strictly speaking, superfluous and is only needed for emphasizing stoichiometry when discussing compositionally related substances, such as Examples 2, 3 and 4 above. 

Alternatively, proportions of constituents may be indicated by using oxidation numbers or charge numbers (Section IR-5.4.2). 

For compounds containing more than two elements, further conventions are required to form a compositional name (see Sections IR-5.4 and IR-5.5). 

---

IR-5.2 Stoichiometric names of elements and binary compounds IR-5.3 Names of ions and radicals IR-5.3.1 General IR-5.3.2 Cations IR-5.3.2.1 General IR-5.3.2.2 Monoatomic cations IR-5.3.2.3 Homopolyatomic cations IR-5.3.2.4 Heteropolyatomic cations IR-5.3.3 Anions IR-5.3.3.1 Overview IR-5.3.3.2 Monoatomic anions IR-5.3.3.3 Homopolyatomic anions IR-5.3.3.4 Heteropolyatomic anions IR-5.4 Generalized stoichiometric names... 

---