Nessler’s reagent
Neßler’s reagent is a reagent named after Julius Neßler and is used to detect small amounts of ammonia. It is a 0.09 mol/L solution of potassium tetraiodomercurate(II) (K2) in 2.5 mol/L potassium hydroxide. A yellow coloration indicates the presence of ammonia: at higher concentrations, a brown precipitate may form. The sensitivity as a spot test is about [...]