How it works
This chemistry naming worksheet has 58 questions on naming compounds: ionic compounds, metals that need a Roman numeral, polyatomic ions, molecular compounds with Greek prefixes, and acids, asked formula to name and name to formula.
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Five sets
Ionic covers metals with one charge, such as sodium chloride. Roman numerals works out the metal's charge, as in iron(III) oxide. Polyatomic ions adds brackets. Molecular uses prefixes. Rules and acids asks which rule applies.
Print or practise
Practice brings a missed question back until you get it right. The sheet on screen is what prints: remove a question, add more up to all 58, and tick With answer key.
- Metal plus nonmetal: no prefixes. Two nonmetals: prefixes.
- To find a Roman numeral, total the anion charges and share them among the metal atoms.
- Put brackets round a polyatomic ion only when there is more than one of it.
Questions and answers
How do you name an ionic compound?
Name the metal, then the nonmetal with -ide, or the polyatomic ion's own name. Add a Roman numeral only when the metal can have more than one charge: CaCl₂ is calcium chloride, FeCl₃ is iron(III) chloride.
When do you use prefixes like di- and tri-?
Only for molecular compounds of two nonmetals. N₂O₄ is dinitrogen tetroxide. Mono- is dropped on the first element, so CO is carbon monoxide.
How are acids named?
A binary acid takes hydro- and -ic: HCl(aq) is hydrochloric acid. An acid from an -ate ion ends in -ic (sulfuric acid); one from an -ite ion ends in -ous (nitrous acid).