Naming Compounds
Ionic compounds are named cation first with anion suffixes (-ide, or -ate/-ite for polyatomic ions); covalent compounds take Greek prefixes; acids convert their anion endings (-ide to hydro…-ic, -ate to -ic, -ite to -ous).
Convert between name and formula for each compound below.
Common Questions
How do you name ionic compounds?
Write the cation (metal) name first, then the anion (nonmetal) name with an -ide suffix. For transition metals, include the charge in Roman numerals: iron(III) chloride. For polyatomic ions, use the ion name directly.
How do you name covalent (molecular) compounds?
Use Greek prefixes to indicate the number of each atom: mono- (1), di- (2), tri- (3), tetra- (4), penta- (5), hexa- (6). The first element drops the mono- prefix. The second element gets an -ide suffix. Example: dinitrogen pentoxide.
What is the difference between ionic and covalent naming?
Ionic compounds (metal + nonmetal) do not use Greek prefixes — the charges determine the ratio. Covalent compounds (two nonmetals) use Greek prefixes because multiple ratios are possible.
How do you write a chemical formula from a compound name?
For ionic: determine the ions and their charges, then find the ratio that balances charges. For covalent: the prefixes directly tell you the subscripts. For example, carbon tetrachloride = CCl4.