ethyldichloroarsine
{{chembox
| Watchedfields = changed
| verifiedrevid = 443937196
| ImageFileR1 = EtAsCl2.png
| ImageFileL1 = Ethyldichloroarsine 3D.png
| PIN = Ethylarsonous dichloride
| OtherNames = ED
Dichloroethylarsane; DICK
|Section1={{Chembox Identifiers
| CASNo_Ref = {{cascite|correct|??}}
| CASNo = 598-14-1
| PubChem = 11711
| ChemSpiderID = 11219
| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
| EC_number = 209-919-3
| RTECS = CH3500000
| UNNumber = 1892
| UNII = 4Z7627500U
| StdInChI=1S/C2H5AsCl2/c1-2-3(4)5/h2H2,1H3
| StdInChIKey = LQSFEOMOHFPNEB-UHFFFAOYSA-N
| SMILES = CC[As](Cl)Cl
}}
|Section2={{Chembox Properties
| Formula = C2H5AsCl2
| MolarMass = 174.8893 g/mol
| Appearance = Colorless, mobile liquid
| Density = 1.742 @ 14 °C
| MeltingPtC = -65
| BoilingPtC = 156
| BoilingPt_notes = (decomposes)
| Solubility = Soluble in alcohol, benzene, ether, and water}}
|Section3={{Chembox Hazards
| MainHazards = Highly toxic, irritant
| FlashPt =
| AutoignitionPt =
}}
}}
Ethyldichloroarsine, sometimes abbreviated as "ED" and "CY" and also known as ethyl Dick,{{cite journal | vauthors = Wood JR | title = Chemical Warfare-A Chemical and Toxicological Review | journal = American Journal of Public Health and the Nation's Health | volume = 34 | issue = 5 | pages = 455–60 | date = May 1944 | pmid = 18015982 | pmc = 1625133 | doi = 10.2105/AJPH.34.5.455 }} is an organoarsenic compound with the formula CH3CH2AsCl2. This colourless volatile liquid is a highly toxic obsolete vesicant or blister agent that was used during World War I in chemical warfare.{{cite web | title = Methyldichloroarsine | url = http://www.northshore.org/healthresources/encyclopedia/bioterrorism/ch018200.aspx | archive-url = https://web.archive.org/web/20110307031414/http://www.northshore.org/healthresources/encyclopedia/bioterrorism/ch018200.aspx | archive-date=March 7, 2011 | publisher = NorthShore University HealthSystem }} The molecule is pyramidal with the Cl-As-Cl and C-As-Cl angles approaching 90° (see image). Ethyldichloroarsine has high chronic toxicity, similar to lewisite.{{cite journal | vauthors = Okumura A, Takada Y, Watanabe S, Hashimoto H, Ezawa N, Seto Y, Takayama Y, Sekioka R, Yamaguchi S, Kishi S, Satoh T, Kondo T, Nagashima H, Nagoya T | display-authors = 6 | title = In-Line Reactions and Ionizations of Vaporized Diphenylchloroarsine and Diphenylcyanoarsine in Atmospheric Pressure Chemical Ionization Mass Spectrometry | journal = Journal of the American Society for Mass Spectrometry | volume = 27 | issue = 7 | pages = 1219–26 | date = July 2016 | pmid = 27098411 | doi = 10.1007/s13361-016-1394-0 | bibcode = 2016JASMS..27.1219O }}