Potassium tetraiodomercurate(II) is an inorganic compound consisting of potassium cations and the tetraiodomercurate(II) anion. It is mainly 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.[2]
Crystallizing from a concentrated aqueous solution of mercuric iodide with potassium iodide is the monohydrate K2HgI4.H2O, which is pale orange.[3] In aqueous solution this triodido complex adds iodide to give the tetrahedral tetraiodo dianion.[4]
Solutions of K2HgI4 react with Cu(I) salts to give Cu2HgI4.[5]
Nessler's reagent
Named after Julius Neßler (Nessler), an alkaline solution of K2HgI4 is called Nessler's reagent. This pale solution becomes deeper yellow in the presence of ammonia. At higher concentrations, a brown precipitate may form. The sensitivity as a spot test is about 0.3 μg NH3 in 2 μL.[6]
^Vogel, Arthur I.; Svehla, G. (1979), Vogel's Textbook of Macro and Semimicro Qualitative Inorganic Analysis (5th ed.), London: Longman, ISBN0-582-44367-9
^F. Wagenknecht, R. Juza, "Potassium Triiodomercurate(II)" in Handbook of Preparative Inorganic Chemistry, 2nd Ed. Edited by G. Brauer, Academic Press, 1963, NY. Vol. 1. p. 1100.
^Mok, K. F.; McKee, V. (1990). "Structure of a dipotassium tetraiodomercurate(II) salt with dibenzo-18-crown-6". Acta Crystallographica C. 46 (11): 2078–2081. doi:10.1107/S0108270190003742.
^F. Wagenknecht, R. Juza, "Copper(I) Tetraiodomercurate(II)" in Handbook of Preparative Inorganic Chemistry, 2nd Ed. Edited by G. Brauer, Academic Press, 1963, NY. Vol. 1. p. 1100.
^Arthur I. Vogel, A Text-Book of Macro and Semimicro Qualitative Inorganic Analysis, Longmans. Green and Co. 1954, New York-London. page 319.
^Svehla, G. (1979). Vogel's Textbook of Macro and semimicro qualitative inorganic analysis (5th ed.). London: Longman Group. pp. 293–294. ISBN0-582-44367-9.
External links
January 20, 2023
potassium, tetraiodomercurate, inorganic, compound, consisting, potassium, cations, tetraiodomercurate, anion, mainly, used, nessler, reagent, solution, potassium, tetraiodomercurate, hgi4, potassium, hydroxide, used, detect, ammonia, namesiupac, name, potassi. Potassium tetraiodomercurate II is an inorganic compound consisting of potassium cations and the tetraiodomercurate II anion It is mainly 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 2 Potassium tetraiodomercurate II NamesIUPAC name potassium tetraiodidomercurate II Other names potassium mercuric iodide Nessler s reagent principal component IdentifiersCAS Number 7783 33 7 Y3D model JSmol Interactive imageChEBI CHEBI 51568 NChemSpider 22948 NECHA InfoCard 100 029 082EC Number 231 990 4PubChem CID 15980736UNII 7N83S6IU0F YUN number 3287CompTox Dashboard EPA DTXSID30893684InChI InChI 1S Hg 4HI 2K h 4 1H q 2 2 1 p 4 NKey OPCMAZHMYZRPID UHFFFAOYSA J NSMILES K K I Hg 2 I I IPropertiesChemical formula K2 HgI4 1 Appearance yellow crystalsOdor odorlessDensity 4 29 g cm3Solubility in water very solubleSolubility soluble in alcohol ether acetoneHazardsSafety data sheet SDS External MSDS for Nessler s reagentRelated compoundsOther anions Mercury II iodideExcept where otherwise noted data are given for materials in their standard state at 25 C 77 F 100 kPa N verify what is Y N Infobox references Contents 1 Preparation and structure 2 Nessler s reagent 3 References 4 External linksPreparation and structure EditCrystallizing from a concentrated aqueous solution of mercuric iodide with potassium iodide is the monohydrate K2HgI4 H2O which is pale orange 3 In aqueous solution this triodido complex adds iodide to give the tetrahedral tetraiodo dianion 4 Solutions of K2HgI4 react with Cu I salts to give Cu2HgI4 5 Nessler s reagent EditNamed after Julius Nessler Nessler an alkaline solution of K2HgI4 is called Nessler s reagent This pale solution becomes deeper yellow in the presence of ammonia At higher concentrations a brown precipitate may form The sensitivity as a spot test is about 0 3 mg NH3 in 2 mL 6 NH4 2 HgI4 2 4 OH iodide of Millon s base HgO Hg NH2 I 7 I 3 H2OThe formula for the brown precipitate a derivative of Millon s base is given as 3HgO Hg NH3 2I2 and as NH2 Hg2I3 clarification needed 7 References Edit Lide David R ed 2009 CRC Handbook of Chemistry and Physics 90th ed Boca Raton Florida CRC Press p 4 82 ISBN 978 1 4200 9084 0 Vogel Arthur I Svehla G 1979 Vogel s Textbook of Macro and Semimicro Qualitative Inorganic Analysis 5th ed London Longman ISBN 0 582 44367 9 F Wagenknecht R Juza Potassium Triiodomercurate II in Handbook of Preparative Inorganic Chemistry 2nd Ed Edited by G Brauer Academic Press 1963 NY Vol 1 p 1100 Mok K F McKee V 1990 Structure of a dipotassium tetraiodomercurate II salt with dibenzo 18 crown 6 Acta Crystallographica C 46 11 2078 2081 doi 10 1107 S0108270190003742 F Wagenknecht R Juza Copper I Tetraiodomercurate II in Handbook of Preparative Inorganic Chemistry 2nd Ed Edited by G Brauer Academic Press 1963 NY Vol 1 p 1100 Arthur I Vogel A Text Book of Macro and Semimicro Qualitative Inorganic Analysis Longmans Green and Co 1954 New York London page 319 Svehla G 1979 Vogel s Textbook of Macro and semimicro qualitative inorganic analysis 5th ed London Longman Group pp 293 294 ISBN 0 582 44367 9 External links EditIARC Monograph Mercury and Mercury Compounds National Pollutant Inventory Mercury and compounds fact sheet Retrieved from https en wikipedia org w index php title Potassium tetraiodomercurate II amp oldid 1116854910, wikipedia, wiki, book, books, library,
