Editing Ammonia (section)

=== Ammonia in solution ===
{{Main|Ammonia solution}}
Ammonia and ammonium salts can be readily detected, in very minute traces, by the addition of [[Nessler's solution]], which gives a distinct yellow colouration in the presence of the slightest trace of ammonia or ammonium salts. The amount of ammonia in ammonium salts can be estimated quantitatively by distillation of the salts with [[sodium hydroxide|sodium]] (NaOH) or [[potassium hydroxide]] (KOH), the ammonia evolved being absorbed in a known volume of standard [[sulfuric acid]] and the excess of acid then determined [[volumetric analysis|volumetrically]]; or the ammonia may be absorbed in [[hydrochloric acid]] and the ammonium chloride so formed precipitated as [[ammonium hexachloroplatinate]], {{chem2|[NH4]2[PtCl6]}}.{{sfn|Chisholm|1911|p=863}}