How do qualitaitve analysis work?

jd12345

I usually see a specific functional group is reacted with a transition metal to forma complex producing bright colours - and we distinguish groups based on such reactions and colours

But the complex will be formed with any nucleophile ( ligand ) right?. Example:- cerric ammonium test is done for alcohols. IT forms a complex with alcohol as the the -OH group acts as a ligand producing red colour.
But this red colour will be formed with any nucleophile as any other ligand can form the complex.

Same with other functional groups. I dont see how complex formation distinguishes these functional groups

Borek

Different ligands produce different colors (please read about crystal field theory), correctly selecting the transition metal and conditions it is possible to make the reaction quite specific.

But I suppose false positives are possible in some cases.