Editing CS gas (section)

{{Short description|Chemical compound}}
{{About|the tear gas|the compound with the molecular formula CS|Carbon monosulfide}}
{{Good article}}
{{Use dmy dates|date=June 2020}}
{{Use British English|date=November 2013}} 
{{Chembox
| data page pagename = none
| Watchedfields = changed
| verifiedrevid = 451284250
| ImageFile = CS gas.svg
| ImageClass = skin-invert-image
| ImageSize = 
| ImageName = Skeletal formula of CS gas
| ImageFile1 = CS-gas-3D-vdW.png
| ImageClass1 = bg-transparent
| ImageSize1 = 
| ImageName1 = Space-filling model of CS gas
| PIN = [(2-Chlorophenyl)methylidene]propanedinitrile
| OtherNames = 2-(2-Chlorobenzylidene)malononitrile<br />2-Chlorobenzalmalononitrile<br />''o''-Chlorobenzylidene malononitrile<br />Tear gas<!--OCBM <br />TL-238 <br />EA-1779 unchecked unsourced-->
<!-- 2022-01-05: from CS gas (data page), unchecked unsourced so no showing here. {{ubl|2-Chlorobenzalmalononitrile|(''o''-Chlorobenzal)malononitrile|''o''-Chlorobenzylidenemalonic nitrile|2-Chlorobenzylidenemaloninitrile|(''o''-Chlorobenzylidene)malonitrile|2-Chlorobenzylidenemalononitrile|2-(2-Chlorobenzylidene)malononitrile|(''o''-Chlorobenzylidene)malononitrile|''ortho''-Chlorobenzylidenemalononitrile|2-2-Chlorobenzylidenepropanedinitrile|2-Chloro BMN|β,β-Dicyano-''o''-chlorostyrene|NCI-C55118|Tear gas|USAF KF-11}} --->
|Section1={{Chembox Identifiers
| IUPHAR_ligand = 4158
| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
| ChemSpiderID = 16644
| PubChem = 17604
| EC_number = 220-278-9
| RTECS = OO3675000
| UNNumber = 2810, 3276, 2811
| UNII = D8317IAV7Q
| ChEMBL = 1256101
| InChI = 1/C10H5ClN2/c11-10-4-2-1-3-9(10)5-8(6-12)7-13/h1-5H
| InChIKey = JJNZXLAFIPKXIG-UHFFFAOYAA
| CASNo_Ref = {{cascite|correct|??}}
| CASNo = 2698-41-1
| StdInChI_Ref = {{stdinchicite|correct|chemspider}}
| StdInChI = 1S/C10H5ClN2/c11-10-4-2-1-3-9(10)5-8(6-12)7-13/h1-5H
| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}
| StdInChIKey = JJNZXLAFIPKXIG-UHFFFAOYSA-N
| SMILES = Clc1ccccc1\C=C(/C#N)C#N
}}
|Section2={{Chembox Properties
| Formula = C<sub>10</sub>H<sub>5</sub>ClN<sub>2</sub><ref name="USArmy">{{cite web | last = Williams | first = Kenneth E. | name-list-style = vanc | url = http://www.waco93.com/detcs.pdf | archive-url = https://web.archive.org/web/20070926011533/http://www.waco93.com/detcs.pdf  | archive-date = 26 September 2007 | title = Detailed Facts About Tear Agent O-Chlorobenzylidene Malononitrile (CS)] | work = U.S. Army Center for Health Promotion and Preventive Medicine }}</ref>
| MolarMass = 188.6&nbsp;g/mol<ref name=UweHeinrich>{{cite web | vauthors = Heinrich U | url = http://www.veritagiustizia.it/docs/gas_cs/CS_Effects_Waco.pdf | title = Possible lethal effects of CS tear gas on Branch Davidians during the FBI raid on the Mount Carmel compound near Waco, Texas | date = September 2000 | access-date = 23 September 2007 | archive-date = 25 December 2014 | archive-url = https://web.archive.org/web/20141225230238/http://www.veritagiustizia.it/docs/gas_cs/CS_Effects_Waco.pdf | url-status = live }}</ref>
| Appearance = White crystalline powder<br />Colourless gas when burned
| Odor = Pepper-like<ref name=PGCH />
| Density = 1.04&nbsp;g/cm<sup>3</sup>
| MeltingPtC = 93
| MeltingPt_notes =
| BoilingPtC = 310
| BoilingPt_ref = <ref>{{cite book|url=https://books.google.com/books?id=y2FwGRVMW5kC&pg=PA138|page=138|title=Compendium of Chemical Warfare Agents|author=Hoenig, Steven L.|publisher=Springer|year=2006|isbn=978-0-387-34626-7}}</ref>
| VaporPressure = 3.4×10<sup>−5</sup>{{nbsp}}[[mmHg]] at 20&nbsp;°C
| Solubility = Insoluble
 }}
|Section7={{Chembox Hazards
| NFPA-H = 2
| NFPA-F = 1
| NFPA-R = 0
| GHSPictograms = {{GHS05}}{{GHS06}}{{GHS07}}{{GHS08}}{{GHS09}}
| GHSSignalWord = Danger
| HPhrases = {{H-phrases|302|314|330|335|372|410}}
| PPhrases = {{P-phrases|260|261|264|270|271|273|280|284|301+312|301+330+331|303+361+353|304+340|305+351+338|310|312|314|320|321|330|363|391|403+233|405|501}}
| PEL = TWA 0.05{{nbsp}}ppm (0.4{{nbsp}}mg/m<sup>3</sup>)<ref name=PGCH>{{PGCH|0122}}</ref>
| IDLH = 2{{nbsp}}mg/m<sup>3</sup><ref name=PGCH />
| REL = C 0.05{{nbsp}}ppm (0.4{{nbsp}}mg/m<sup>3</sup>) [skin]<ref name=PGCH />
| LCLo = {{ubl
 | 1806{{nbsp}}mg/m<sup>3</sup> (rat, 45{{nbsp}}min)
 | 2753{{nbsp}}mg/m<sup>3</sup> (mouse, 20{{nbsp}}min)
 | 1802{{nbsp}}mg/m<sup>3</sup> (rabbit, 10{{nbsp}}min)
 | 2326{{nbsp}}mg/m<sup>3</sup> (guinea pig, 10{{nbsp}}min)<ref>{{IDLH|2698411|o-Chlorobenzylidene malononitrile}}</ref>
 }}
}}
|Section8={{Chembox Related
| OtherCompounds = [http://www.aist.go.jp/RIODB/SDBS/cgi-bin/direct_frame_top.cgi?lang=eng SDBS]
5-chloro-2-quinolinecarbonitrile <br /> 6-chloro-2-quinolinecarbonitrile <br /> 7-chloro-2-quinolinecarbonitrile}}
}}

The compound '''2-chlorobenzalmalononitrile''' (also called '''''o''-chlorobenzylidene malononitrile'''; chemical formula: C<sub>10</sub>H<sub>5</sub>ClN<sub>2</sub>), a [[cyanocarbon]], is the defining component of the [[lachrymatory agent]] commonly referred to as '''CS gas''', a [[tear gas]] which is used as a [[riot control agent]], and is banned for use in warfare due to the [[1925 Geneva Protocol]].

Exposure causes a burning sensation and tearing of the eyes to the extent that the subject cannot keep their eyes open, and a burning irritation of the mucous membranes of the nose, mouth and throat, resulting in profuse coughing, nasal mucus discharge, disorientation, and difficulty breathing, partially incapacitating the subject. CS gas is an [[aerosol]] of a [[volatility (chemistry)|volatile]] [[solvent]] (a substance that dissolves other active substances and that easily evaporates) and 2-chlorobenzalmalononitrile, which is a solid compound at room temperature. CS gas is generally accepted as being [[Non-lethal force|non-lethal]].