A chloroanion is an anion that contains an element and chlorine atoms.

They can occur in salts, or in solution, but not as pure acids.

[3] Some chloroanions are stable in a solution in water, whereas others are decomposed.

They may be stable in a molten salt, such as an ionic liquid.

[4] In the solid form some are only stable with large cations, as when there are small cations they may form two separate chloride salt phases.