Naming Compounds

The first step in naming any compound is to determine if the compound is ionic or molecular.

Naming Binary Molecular Compounds

Naming Ionic Compounds

Step 1: Name the positive ion (cation)

	Cations formed from metal ions have the same name as the metal.
	If a metal can form cations of different charges, the positive charge is given by roman numeral in paratheses, such as Fe²⁺ is Iron(II). An older method uses -ous for lower charge, -ic for higher charge.
	Cations formed from non-metals have names that end in -ium, such as ammonium (NH₄⁺)

Step 2: Name the negative ion (anion)

Monatomic anions drop the end of the name of the element and add -ide, such as oxide (O^2-).

A few simple polyatomic anions also end in -ide, such as hydroxide (OH^-) and peroxide (O₂^2-).

Polyatomic anions containing oxygen have names ending in -ate or -ite. These are oxyanions.

-ate is used for most common oxyanion, -ite is used for anion with same charge but one less oxygen atom.

Prefixes are used when the series extends to four members, such as with the halogens.

	Per- prefix when the anion has one more oxygen atom than the most common -ate.
	Hypo- prefix when the anion has one less oxygen atom than the -ite suffix.

Anions derived from adding H+ to an oxyanion are named by adding the word hydrogen or dihydrogen.

Step 3: Name the ionic compound by using the cation followed by the anion names.

Naming Acids Compounds