Name the complex ion [al(cn)6]3−. the oxidation number of aluminum is +3.

Hexacyanoaluminate III

Explanation:

A complex ion consists of a central metal ion and ligands. The number of ligands present is known as the coordination number of the complex ion. Complex ions could be positive or negative.

The ion in the question is a negative complex ion. Negative complex ions have their names ending with -ate. The number of ligands is first mentioned, followed by the name of the ligand(s) and lastly the central metal is named ending in -ate followed by its oxidation number in the complex ion.