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Potassium mercuric iodide - is an inorganic compound consisting of potassium cations and the tetraiodomercurate(II) anion.
P 2380 (OTTO) Potassium mercuric iodide Cas 7783-33-7 - used as Nessler's reagent, a 0.09 mol/L solution of potassium tetraiodomercurate(II) (K2[HgI4]) in 2.5 mol/L potassium hydroxide, used to detect ammonia.