Ammonia, NH 3, is an alkaline gas and so turns damp red litmus paper blue. Ammonium ions (NH 4 +) – found in ammonium compounds such as ammonium chloride, ammonium nitrate and ammonium sulfate ...

A cotton swab is dipped into concentrated hydrochloric acid (producing hydrogen chloride gas) while a second on is dipped into concentrated aqueous ammonia (producing ammonia gas). Both cotton swabs ...

Method: Dip a glass rod in concentrated hydrochloric acid and put this in a sample of the gas. Result: If ammonia is present, a white ‘smoke’ of ammonium chloride is observed.