Radicals A Radical is a charged group of atoms. Radicals often remain grouped together during chemical reactions.
Radicals have a valency in the same way that ions have a valency.
Some of the common Radicals are listed below. When working out the formula of compounds containing radicals just think of the radical as a single unit as if it is an ordinary ion. The Nitrate radical is treated as if it is a single ion. The 'bracket' is placed around the radical for clarity. If you were working out the number of atoms in one molecule of Calcium Nitrate you need to remember that the '2' outside the bracket means two radicals of Nitrate which means two of everything inside the bracket.