Editing Lewisite (section)

==Chemical reactions==
The compound is prepared by the addition of [[arsenic trichloride]] to [[acetylene]] in the presence of a suitable catalyst:

{{block indent|AsCl<sub>3</sub> + C<sub>2</sub>H<sub>2</sub> → ClCHCHAsCl<sub>2</sub> (Lewisite)}}

This chemical process can occur a second or third time, giving [[lewisite 2]] and [[lewisite 3]] as byproducts.<ref name=":3">Chemistry of Sulfur Mustard and Lewisite https://www.ncbi.nlm.nih.gov/books/NBK236079/</ref>

Lewisite, like other arsenous chlorides, [[hydrolysis|hydrolyses]] in water to form [[hydrochloric acid]] and [[chlorovinylarsenous oxide]] (a less-powerful blister agent):<ref name=":0"/>

{{block indent|ClCHCHAsCl<sub>2</sub> + 2 H<sub>2</sub>O → ClCHCHAs(OH)<sub>2</sub> + 2 HCl}}

This reaction is accelerated in alkaline solutions, and forms acetylene and [[trisodium arsenate]].<ref name=":0"/>

Lewisite reacts with metals to form hydrogen gas. It is combustible, but difficult to ignite.<ref name=":0"/>