Zyklon B
Zyklon B (German pronunciation: [tsykloːn ˈbeː]; anglicized. US pronunciation: 
i/ˈzaɪklɒn ˈbiː/ or translated Cyclone B) was the trade name of a cyanide-based pesticide invented in Germany in the early 1920s. It consisted of hydrogen cyanide (prussic acid), as well as a cautionary eye irritant and one of several adsorbents such as diatomaceous earth. The product is infamous for its use by Nazi Germany during the Holocaust to murder approximately one million people in gas chambers installed at Auschwitz-Birkenau, Majdanek, and other extermination camps.
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