The IUPAC (International Union of Pure and Applied Chemistry) convention is used to assign names to chemical compounds. Scientists from around the world formed IUPAC because they recognized the need for standardization in chemistry. IUPAC sets the guidelines for how compounds are named.

There are two main divisions of compounds. The first division are covalent compounds, which are usually composed of only nonmetal species. Electrons are shared between the atoms in a covalent compound. The sharing of electrons between the atoms result in covalent bonds. Some examples are CO, NO₂, SCl₂, CCl₄. The smallest discete unit of a covalent compound is the molecule.

The second division are ionic compounds, also called salts, which are usually composed of both metal and nonmetal species such as NaCl, MgO, K₂SO4, and NaOH. Exceptions would be salts that contain ammonium. Ammonium chloride (NH₄Cl), ammonium nitrate (NH₄NO₃), etc. are also ionic compounds. Formulas for ionic compounds show the simplest whole number ratio between cations and anions (empirical formula). This is called the formula unit.

The differences in the bonding characteristics of the two groups of compounds will be discussed in detail later. For now you need to focus on differentiating between simple covalent and ionic compounds when presented with a chemical formula and learn the basic rules for naming these compounds.

Go to Naming Binary Covalent Compounds
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Study Guide List for General Chemistry 1