Hydrogen chloride - wikipedia Hydrogen chloride This article is about the gas. For the aqueous solution, see hydrochloric acid. Hydrogen chloride Names IUPAC name Hydrogen chloride Other names Hydrochloric acid gas Hydrochloric gas Hydrochloride Identifiers CAS Number 7647 - 01 - 0 3D model ( JSmol ) Interactive image Beilstein Reference 1098214 ChEBI CHEBI : 17883 ChemSpider 307 ECHA InfoCard 100.028. 723 EC Number 231 - 595 - 7 Gmelin Reference 322 KEGG D02057 MeSH Hydrochloric + acid RTECS number MW4025000 UNII QTT17582CB UN number 1050 InChI InChI = 1S / HCl / h1H Key : VEXZGXHMUGYJMC - UHFFFAOYSA - N InChI = 1 / HCl / h1H Key : VEXZGXHMUGYJMC - UHFFFAOYAT SMILES Cl Properties Chemical formula HCl Molar mass 36.46 g / mol Appearance Colorless gas Odor pungent ; sharp and burning Density 1.49 g L Melting point − 114.22 ° C ( − 173.60 ° F ; 158.93 K ) Boiling point − 85.05 ° C ( − 121.09 ° F ; 188.10 K ) Solubility in water 823 g / L ( 0 ° C ) 720 g / L ( 20 ° C ) 561 g / L ( 60 ° C ) Solubility soluble in methanol, ethanol, ether Vapor pressure 4352 kPa ( at 21.1 ° C ) Acidity ( pK ) - 3.0 ; - 5.9 ( ± 0.4 ) Basicity ( pK ) 17.0 Refractive index ( n ) 1.0004456 ( gas ) 1.254 ( liquid ) Viscosity 0.311 cP ( − 100 ° C ) Structure Molecular shape linear Dipole moment 1.05 D Thermochemistry Specific heat capacity ( C ) 0.7981 JK g Std molar entropy ( S ) 186.902 JK mol Std enthalpy of formation ( Δ H ) -- 92.31 kJ mol Std enthalpy of combustion ( Δ H ) -- 95.31 kJ mol Pharmacology ATC code A09AB03 ( WHO ) B05XA13 ( WHO ) Hazards Safety data sheet JT Baker MSDS GHS pictograms GHS signal word Danger GHS hazard statements H280, H314, H331 GHS precautionary statements P261, P280, P305 + 351 + 338, P310, P410 + 403 NFPA 704 0 ACID Lethal dose or concentration ( LD, LC ) : LD ( median dose ) 238 mg / kg ( rat, oral ) LC ( median concentration ) 3124 ppm ( rat, 1 hr ) 1108 ppm ( mouse, 1 hr ) LC ( lowest published ) 1300 ppm ( human, 30 min ) 4416 ppm ( rabbit, 30 min ) 4416 ppm ( guinea pig, 30 min ) 3000 ppm ( human, 5 min ) US health exposure limits ( NIOSH ) : PEL ( Permissible ) C 5 ppm ( 7 mg / m ) REL ( Recommended ) C 5 ppm ( 7 mg / m ) IDLH ( Immediate danger ) 50 ppm Related compounds Related compounds Hydrogen fluoride Hydrogen bromide Hydrogen iodide Hydrogen astatide Except where otherwise noted, data are given for materials in their standard state ( at 25 ° C ( 77 ° F ), 100 kPa ). N verify ( what is ? ) Infobox references The compound hydrogen chloride has the chemical formula H Cl and as such is a hydrogen halide. At room temperature, it is a colorless gas, which forms white fumes of hydrochloric acid upon contact with atmospheric water vapor. Hydrogen chloride gas and hydrochloric acid are important in technology and industry. Hydrochloric acid, the aqueous solution of hydrogen chloride, is also commonly given the formula HCl. Contents 1 Chemistry 1.1 Structure and properties 2 Production 2.1 Direct synthesis 2.2 Organic synthesis 2.3 Laboratory methods 3 Applications 4 History 5 Safety 6 See also 7 References 8 External links Chemistry Hydrochloric acid fumes turning pH paper red showing that the fumes are acidic Hydrogen chloride is a diatomic molecule, consisting of a hydrogen atom H and a chlorine atom Cl connected by a polar covalent bond. The chlorine atom is much more electronegative than the hydrogen atom, which makes this bond polar. Consequently, the molecule has a large dipole moment with a negative partial charge ( δ − ) at the chlorine atom and a positive partial charge ( δ + ) at the hydrogen atom. In part because of its high polarity, HCl is very soluble in water ( and in other polar solvents ). It is polar covalent instead of Ionic because the differences in hydrogen and chlorines electronegativity is small enough that a complete ionic bond does n't form. Any electronegativity between. 6 and 1.67 creates a polar covalent bond. Upon contact, H O and HCl combine to form hydronium cations H O and chloride anions Cl through a reversible chemical reaction : HCl + H O → H O + Cl The resulting solution is called hydrochloric acid and is a strong acid. The acid dissociation or ionization constant, K, is large, which means HCl dissociates or ionizes practically completely in water. Even in the absence of water, hydrogen chloride can still act as an acid. For example, hydrogen chloride can dissolve in certain other solvents such as methanol, protonate molecules or ions, and serve as an acid - catalyst for chemical reactions where anhydrous ( water - free ) conditions are desired. HCl + CH OH → CH O H + Cl Because of its acidic nature, hydrogen chloride is a corrosive substance, particularly in the presence of moisture. Structure and properties The structure of solid DCl, as determined by neutron diffraction of DCl powder at 77 K. DCl was used instead of HCl because the deuterium nucleus is easier to detect than the hydrogen nucleus. The `` infinite '' chains of DCl are indicated by the dashed lines. Frozen HCl undergoes phase transition at 98.4 K. X-ray powder diffraction of the frozen material shows that the material changes from an orthorhombic structure to a cubic one during this transition. In both structures the chlorine atoms are in a face - centered array. However, the hydrogen atoms could not be located. Analysis of spectroscopic and dielectric data, and determination of the structure of DCl ( deuterium chloride ) indicates that HCl forms zigzag chains in the solid, as does HF ( see figure on right ). Solubility of HCl ( g / L ) in common solvents Temperature ( ° C ) 0 20 30 50 Water 823 720 673 596 Methanol 513 470 430 Ethanol 454 410 381 Ether 356 249 195 Infrared ( IR ) absorption spectrum One doublet in the IR spectrum resulting from the isotopic composition of chlorine The infrared spectrum of gaseous hydrogen chloride, shown on the left, consists of a number of sharp absorption lines grouped around 2886 cm ( wavelength ~ 3.47 μm ). At room temperature, almost all molecules are in the ground vibrational state v = 0. Including anharmonicity the vibrational energy can be written as. E v i b = h ν e ⋅ ( v + 1 2 ) + h x e ν e ⋅ ( v + 1 2 ) 2 ( displaystyle E_ ( mathrm ( vib ) ) = h \nu _ ( e ) cdot left ( v+ ( \tfrac ( 1 ) ( 2 ) ) \right ) + hx_ ( e ) \nu _ ( e ) cdot left ( v+ ( \tfrac ( 1 ) ( 2 ) ) \right ) ^ ( 2 ) ) To promote an HCl molecule from the v = 0 to the v = 1 state, we would expect to see an infrared absorption about ν = ν + 2x ν = 2880 cm. However, this absorption corresponding to the Q - branch is not observed due to it being forbidden by symmetry. Instead, two sets of signals ( P - and R - branches ) are seen owing to a simultaneous change in the rotational state of the molecules. Because of quantum mechanical selection rules, only certain rotational transitions are permitted. The states are characterized by the rotational quantum number J = 0, 1, 2, 3,... selection rules state that ΔJ is only able to take values of ± 1. E ( J ) r o t = h ⋅ B ⋅ J ( J + 1 ) ( displaystyle E ( J ) _ ( mathrm ( rot ) ) = h cdot B cdot J ( J + 1 ) ) The value of the rotational constant B is much smaller than the vibrational one ν, such that a much smaller amount of energy is required to rotate the molecule ; for a typical molecule, this lies within the microwave region. However, the vibrational energy of HCl molecule places its absorptions within the infrared region, allowing a spectrum showing the rovibrational transitions of this molecule to be easily collected using an infrared spectrometer with a gas cell. The latter can even be made of quartz as the HCl absorption lies in a window of transparency for this material. Naturally abundant chlorine consists of two isotopes, Cl and Cl, in a ratio of approximately 3 : 1. While the spring constants are identical within experimental error, the reduced masses are different causing measurable differences in the rotational energy, thus doublets are observed on close inspection of each absorption line, weighted in the same ratio of 3 : 1. Production This section does not cite any sources. Please help improve this section by adding citations to reliable sources. Unsourced material may be challenged and removed. ( November 2015 ) Most hydrogen chloride produced on an industrial scale is used for hydrochloric acid production. Direct synthesis Play media Flame inside HCl oven In the chlor - alkali industry, brine ( mixture of sodium chloride and water ) solution is electrolyzed producing chlorine ( Cl ), sodium hydroxide, and hydrogen ( H ) : 2 NaCl + 2 H O → Cl + 2 NaOH + H The pure chlorine gas can be combined with hydrogen to produce hydrogen chloride in the presence of UV light : Cl ( g ) + H ( g ) → 2 HCl ( g ) As the reaction is exothermic, the installation is called an HCl oven or HCl burner. The resulting hydrogen chloride gas is absorbed in deionized water, resulting in chemically pure hydrochloric acid. This reaction can give a very pure product, e.g. for use in the food industry. Organic synthesis The largest production of hydrochloric acid is integrated with the formation of chlorinated and fluorinated organic compounds, e.g., Teflon, Freon, and other CFCs, as well as chloroacetic acid and PVC. Often this production of hydrochloric acid is integrated with captive use of it on - site. In the chemical reactions, hydrogen atoms on the hydrocarbon are replaced by chlorine atoms, whereupon the released hydrogen atom recombines with the spare atom from the chlorine molecule, forming hydrogen chloride. Fluorination is a subsequent chlorine - replacement reaction, producing again hydrogen chloride : R − H + Cl → R − Cl + HCl R − Cl + HF → R − F + HCl The resulting hydrogen chloride gas is either reused directly or absorbed in water, resulting in hydrochloric acid of technical or industrial grade. Laboratory methods Small amounts of HCl gas for laboratory use can be generated in an HCl generator by dehydrating hydrochloric acid with either sulfuric acid or anhydrous calcium chloride. Alternatively, HCl can be generated by the reaction of sulfuric acid with sodium chloride : NaCl + H SO → NaHSO + HCl This reaction occurs at room temperature. Provided there is NaCl remaining in the generator and it is heated above 200 ° C, the reaction proceeds further : NaCl + NaHSO → HCl + Na SO For such generators to function, the reagents should be dry. HCl can also be prepared by the hydrolysis of certain reactive chloride compounds such as phosphorus chlorides, thionyl chloride ( SOCl ), and acyl chlorides. For example, cold water can be gradually dripped onto phosphorus pentachloride ( PCl ) to give HCl : PCl + H O → POCl + 2 HCl High - purity streams of the gas require lecture bottles or cylinders, both of which can be expensive. In comparison, the use of a generator requires only apparatus and materials commonly available in a laboratory. Applications Most hydrogen chloride is used in the production of hydrochloric acid. It is also an important reagent in other industrial chemical transformations, e.g. : Hydrochlorination of rubber Production of vinyl and alkyl chlorides In the semiconductor industry, it is used to both etch semiconductor crystals and to purify silicon via trichlorosilane ( SiHCl ). It may also be used to treat cotton to delint it, and to separate it from wool. In the laboratory, anhydrous forms of the gas are particularly useful for generating chloride - based Lewis acids, which must be absolutely dry for their Lewis sites to function. It can also be used to dry the corresponding hydrated forms of these materials by passing it over as they are heated ; the materials would otherwise fume HCl gas themselves and decompose. Neither can these hydrates be dried using standard desiccator methods. History Alchemists of the Middle Ages recognized that hydrochloric acid ( then known as spirit of salt or acidum salis ) released vaporous hydrogen chloride, which was called marine acid air. In the 17th century, Johann Rudolf Glauber used salt ( sodium chloride ) and sulfuric acid for the preparation of sodium sulfate, releasing hydrogen chloride gas ( see production, below ). In 1772, Carl Wilhelm Scheele also reported this reaction and is sometimes credited with its discovery. Joseph Priestley prepared hydrogen chloride in 1772, and in 1810 Humphry Davy established that it is composed of hydrogen and chlorine. During the Industrial Revolution, demand for alkaline substances such as soda ash increased, and Nicolas Leblanc developed a new industrial - scale process for producing the soda ash. In the Leblanc process, salt was converted to soda ash, using sulfuric acid, limestone, and coal, giving hydrogen chloride as by - product. Initially, this gas was vented to air, but the Alkali Act of 1863 prohibited such release, so then soda ash producers absorbed the HCl waste gas in water, producing hydrochloric acid on an industrial scale. Later, the Hargreaves process was developed, which is similar to the Leblanc process except sulfur dioxide, water, and air are used instead of sulfuric acid in a reaction which is exothermic overall. In the early 20th century the Leblanc process was effectively replaced by the Solvay process, which did not produce HCl. However, hydrogen chloride production continued as a step in hydrochloric acid production. Historical uses of hydrogen chloride in the 20th century include hydrochlorinations of alkynes in producing the chlorinated monomers chloroprene and vinyl chloride, which are subsequently polymerized to make polychloroprene ( Neoprene ) and polyvinyl chloride ( PVC ), respectively. In the production of vinyl chloride, acetylene ( C H ) is hydrochlorinated by adding the HCl across the triple bond of the C H molecule, turning the triple into a double bond, yielding vinyl chloride. The `` acetylene process '', used until the 1960s for making chloroprene, starts out by joining two acetylene molecules, and then adds HCl to the joined intermediate across the triple bond to convert it to chloroprene as shown here : This `` acetylene process '' has been replaced by a process which adds Cl to one of the double bonds in 1, 3 - butadiene instead, and subsequent elimination produces HCl instead, as well as chloroprene. Safety Hydrogen chloride forms corrosive hydrochloric acid on contact with water found in body tissue. Inhalation of the fumes can cause coughing, choking, inflammation of the nose, throat, and upper respiratory tract, and in severe cases, pulmonary edema, circulatory system failure, and death. Skin contact can cause redness, pain, and severe skin burns. Hydrogen chloride may cause severe burns to the eye and permanent eye damage. The gas, being strongly hydrophilic, can be easily scrubbed from the exhaust gases of a reaction by bubbling it through water, producing useful hydrochloric acid as a byproduct. Any equipment handling hydrogen chloride gas must be checked on a routine basis ; particularly valve stems and regulators. The gas requires the use of specialized materials on all wetted parts of the flow path, as it will interact with or corrode numerous materials hydrochloric acid alone will not ; such as stainless and regular polymers. The U.S. Occupational Safety and Health Administration and the National Institute for Occupational Safety and Health have established occupational exposure limits for hydrogen chloride at a ceiling of 5 ppm ( 7 mg / m ), and compiled extensive information on hydrogen chloride workplace safety concerns. See also Chloride, inorganic salts of hydrochloric acid Gastric acid, hydrochloric acid secreted into the stomach to aid digestion of proteins Hydrochloride, organic salts of hydrochloric acid References Jump up ^ `` hydrogen chloride ( CHEBI : 17883 ) ''. Chemical Entities of Biological Interest ( ChEBI ). UK : European Bioinformatics Institute. Jump up ^ Haynes, William M. ( 2010 ). Handbook of Chemistry and Physics ( 91 ed. ). Boca Raton, Florida : CRC Press. p. 4 -- 67. ISBN 978 - 1439820773. Jump up ^ Hydrogen Chloride. Gas Encyclopaedia. Air Liquide Jump up ^ Tipping, E. ( 2002 ) ( 1 ). Cambridge University Press, 2004. Jump up ^ Trummal, A. ; Lipping, L. ; Kaljurand, I. ; Koppel, I.A. ; Leito, I. `` Acidity of Strong Acids in Water and Dimethyl Sulfoxide '' J. Phys. Chem. A. 2016, 120, 3663 - 3669. doi : 10.1021 / acs. jpca. 6b02253 ^ Jump up to : `` NIOSH Pocket Guide to Chemical Hazards # 0332 ''. National Institute for Occupational Safety and Health ( NIOSH ). ^ Jump up to : `` Hydrogen chloride ''. Immediately Dangerous to Life and Health. National Institute for Occupational Safety and Health ( NIOSH ). Jump up ^ Ouellette, Robert J. ; Rawn, J. David ( 2015 ). Principles of Organic Chemistry. Elsevier Science. pp. 6 --. ISBN 978 - 0 - 12 - 802634 - 2. Jump up ^ Natta, G. ( 1933 ). `` Struttura e polimorfismo degli acidi alogenidrici ''. Gazzetta Chimica Italiana ( in Italian ). 63 : 425 -- 439. Jump up ^ Sándor, E. ; Farrow, R.F.C. ( 1967 ). `` Crystal Structure of Solid Hydrogen Chloride and Deuterium Chloride ''. Nature. 213 ( 5072 ) : 171 -- 172. Bibcode : 1967Natur. 213... 171S. doi : 10.1038 / 213171a0. Jump up ^ Hydrochloric Acid -- Compound Summary. Pubchem Jump up ^ Francisco J. Arnsliz ( 1995 ). `` A Convenient Way To Generate Hydrogen Chloride in the Freshman Lab ''. J. Chem. Educ. 72 ( 12 ) : 1139. Bibcode : 1995JChEd... 72.1139 A. doi : 10.1021 / ed072p1139. Jump up ^ Hartley, Harold ( 1960 ). `` The Wilkins Lecture. Sir Humphry Davy, Bt., P.R.S. 1778 -- 1829 ''. Proceedings of the Royal Society A. 255 ( 1281 ) : 153 -- 180. Bibcode : 1960RSPSA. 255... 153H. doi : 10.1098 / rspa. 1960.0060. Jump up ^ CDC -- NIOSH Pocket Guide to Chemical Hazards Jump up ^ `` Hydrogen Chloride ''. CDC - NIOSH Workplace Safety and Health Topic. March 5, 2012. Retrieved 2016 - 07 - 15. External links Wikimedia Commons has media related to Hydrogen chloride. International Chemical Safety Card 0163 Thames & Kosmos Chem C2000 Experiment Manual Hydrogen compounds H AsO H AsO HAt HSO F HBF HBr HBrO HBrO HBrO HBrO HCl HClO HClO HClO HClO HCN HCNO H CrO / H Cr O H CO H CS HF HFΟ HI HIO HIO HIO HIO HMnO H MoO HNC NaHCO HNCO HNO HNO HNO H N O HNO S H NSO H O H O H O H PO H PO H PO H P O H P O H PtCl H Se H SeO H SeO H SiO H SiF HSCN HNSC H SO H SO H SO H S O H S O H S O H S O CF SO H H Te H TeO H TeO H TiO H Po HCo ( CO ) Molecules detected in outer space Molecules Diatomic Aluminium monochloride Aluminium monofluoride Aluminium monoxide Argonium Carbon monophosphide Carbon monosulfide Carbon monoxide Carborundum Cyanogen radical Diatomic carbon Fluoromethylidynium Hydrogen chloride Hydrogen fluoride Hydrogen ( molecular ) Hydroxyl radical Iron ( II ) oxide Magnesium monohydride cation Methylidyne radical Nitric oxide Nitrogen ( molecular ) Nitrogen monohydride Nitrogen sulfide Oxygen ( molecular ) Phosphorus monoxide Phosphorus mononitride Potassium chloride Silicon carbide Silicon mononitride Silicon monoxide Silicon monosulfide Sodium chloride Sodium iodide Sulfur monohydride Sulfur monoxide Titanium oxide Triatomic Aluminium hydroxide Aluminium isocyanide Amino radical Carbon dioxide Carbonyl sulfide CCP radical Chloronium Diazenylium Dicarbon monoxide Disilicon carbide Ethynyl radical Formyl radical Hydrogen cyanide ( HCN ) Hydrogen isocyanide ( HNC ) Hydrogen sulfide Hydroperoxyl Iron cyanide Isoformyl Magnesium cyanide Magnesium isocyanide Methylene radical Nitrous oxide Nitroxyl Ozone Phosphaethyne Potassium cyanide Protonated molecular hydrogen Sodium cyanide Sodium hydroxide Silicon carbonitride c - Silicon dicarbide Silicon naphthalocyanine Sulfur dioxide Thioformyl Thioxoethenylidene Titanium dioxide Tricarbon Water Four atoms Acetylene Ammonia Cyanic acid Cyanoethynyl Cyclopropynylidyne Formaldehyde Fulminic acid HCCN Hydrogen peroxide Hydromagnesium isocyanide Isocyanic acid Isothiocyanic acid Ketenyl Methylene amidogen Methyl radical Propynylidyne Protonated carbon dioxide Protonated hydrogen cyanide Silicon tricarbide Thioformaldehyde Tricarbon monoxide Tricarbon sulfide Thiocyanic acid Five atoms Ammonium ion Butadiynyl Carbodiimide Cyanamide Cyanoacetylene Cyanoformaldehyde Cyanomethyl Cyclopropenylidene Formic acid Isocyanoacetylene Ketene Methane Methoxy radical Methylenimine Propadienylidene Protonated formaldehyde Protonated formaldehyde Silane Silicon - carbide cluster Six atoms Acetonitrile Cyanobutadiynyl radical E-Cyanomethanimine Cyclopropenone Diacetylene Ethylene Formamide HC N Ketenimine Methanethiol Methanol Methyl isocyanide Pentynylidyne Propynal Protonated cyanoacetylene Seven atoms Acetaldehyde Acrylonitrile Vinyl cyanide Cyanodiacetylene Ethylene oxide Hexatriynyl radical Methylacetylene Methylamine Methyl isocyanate Vinyl alcohol Eight atoms Acetic acid Aminoacetonitrile Cyanoallene Ethanimine Glycolaldehyde Heptatrienyl radical Hexapentaenylidene Methylcyanoacetylene Methyl formate Propenal Nine atoms Acetamide Cyanohexatriyne Cyanotriacetylene Dimethyl ether Ethanol Methyldiacetylene Octatetraynyl radical Propene Propionitrile Ten atoms or more Acetone Benzene Buckminsterfullerene ( C fullerene, buckyball ) C fullerene Cyanodecapentayne Cyanopentaacetylene Cyanotetra - acetylene Ethylene glycol Ethyl formate Methyl acetate Methyl - cyano - diacetylene Methyltriacetylene Propanal n - Propyl cyanide Pyrimidine Deuterated molecules Ammonia Ammonium ion Formaldehyde Formyl radical Heavy water Hydrogen cyanide Hydrogen deuteride Hydrogen isocyanide Methylacetylene Trihydrogen cation Unconfirmed Anthracene Dihydroxyacetone Ethyl methyl ether Glycine Graphene H NCO Linear C Naphthalene cation Phosphine Pyrene Silylidine Related Abiogenesis Astrobiology Astrochemistry Atomic and molecular astrophysics Chemical formula Circumstellar envelope Cosmic dust Cosmic ray Cosmochemistry Diffuse interstellar band Earliest known life forms Extraterrestrial life Extraterrestrial liquid water Forbidden mechanism Helium hydride ion Homochirality Intergalactic dust Interplanetary medium Interstellar medium Photodissociation region Iron -- sulfur world theory Kerogen Molecules in stars Nexus for Exoplanet System Science Organic compound Outer space PAH world hypothesis Panspermia Polycyclic aromatic hydrocarbon ( PAH ) RNA world hypothesis Spectroscopy Tholin Book : Chemistry Category : Astrochemistry Category : Molecules Portal : Astrobiology Portal : Astronomy Portal : Chemistry Chlorine compounds ClF ClF ClF ClNO ClO Cl O ClO ClO F ClO F Cl O Cl O Cl O Cl O HCl SiCl Binary compounds of hydrogen Alkali metal hydrides LiH NaH KH RbH CsH Lithium hydride, LiH ionic metal hydride Beryllium hydride Left ( gas phase ) : BeH covalent metal hydride Right : ( BeH ) ( solid phase ) polymeric metal hydride Borane and diborane Left : BH ( special conditions ), covalent metalloid hydride Right : B H ( standard conditions ), dimeric metalloid hydride Methane, CH covalent nonmetal hydride Ammonia, NH covalent nonmetal hydride Water, H O covalent nonmetal hydride Hydrogen fluoride, HF covalent nonmetal hydride Alkaline earth hydrides Monohydrides BeH MgH CaH SrH BaH BeH MgH CaH SrH BaH Group 13 hydrides Boranes BH Alanes AlH Al H Gallanes GaH Ga H Indiganes InH In H Thallanes TlH Tl H Group 14 hydrides Linear alkanes CH more... Linear alkenes more... Linear alkynes more... Silanes SiH Si H Si H Si H Si H Si H Si H Si H Si H Si H more... Silenes Si H Silynes Si H Germanes GeH Ge H Ge H Ge H Ge H Stannanes SnH Sn H Plumbanes PbH CH CH CH Cycloalkanes Cycloalkenes Annulenes Many more Pnictogen hydrides Azanes NH more... Azenes Phosphanes PH more... Phosphenes Arsanes AsH As H Stibanes SbH Bismuthanes BiH HN NH radical Hydrogen chalcogenides Polyoxidanes H O H O H O H O H O H O H O H O H O H O more... Polysulfanes more... Selanes H Se H Se Tellanes H Te H Te Polanes PoH HO HO HO H O -- O H S = S ( HS ) S+ -- S -- HS HDO D O T O Hydrogen halides HF HCl HBr HI HAt Transition metal hydrides ScH YH YH TiH ZrH HfH VH VH NbH NbH TaH CrH CrH CrH NiH PdH ( x < 1 ) FeH FeH FeH CuH ZnH CdH HgH Lanthanide hydrides LaH LaH CeH CeH PrH PrH NdH NdH SmH SmH EuH GdH GdH TbH TbH DyH DyH HoH HoH ErH ErH TmH TmH YbH YbH LuH LuH Actinide hydrides AcH ThH Th H PaH UH NpH NpH PuH PuH AmH AmH CmH GND : 4147850 - 2 NDL : 00561990 Retrieved from `` https://en.wikipedia.org/w/index.php?title=Hydrogen_chloride&oldid=814222375 '' Categories : Chlorides Halogen - containing natural products Hazardous air pollutants Hydrogen compounds Industrial gases Nonmetal halides Hidden categories : CS1 Italian - language sources ( it ) Chemicals without a PubChem CID ECHA InfoCard ID from Wikidata Articles with changed InChI identifier Chembox having GHS data Articles containing unverified chemical infoboxes Articles needing additional references from November 2015 All articles needing additional references All articles with unsourced statements Articles with unsourced statements from November 2008 Use dmy dates from May 2011 Wikipedia articles with GND identifiers Articles containing video clips Talk Contents About Wikipedia Afrikaans تۆرکجه Bân - lâm - gú Български Bosanski Català Čeština ChiShona Deutsch Eesti Ελληνικά Español فارسی Français Galego 한국어 Հայերեն हिन्दी Hrvatski Bahasa Indonesia ಕನ್ನಡ ქართული Latviešu Magyar मराठी Bahasa Melayu Nederlands 日本 語 Nordfriisk Norsk Occitan Polski Русский Simple English Slovenčina Slovenščina Српски / srpski Srpskohrvatski / српскохрватски ไทย Українська Tiếng Việt 吴语 粵語 中文 Edit links This page was last edited on 7 December 2017, at 15 : 01. 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Question: what gas is given off by concentrated hydrochloric acid
Answer: hydrogen chloride