Ask your students to name you a poison and probably the first one that they mention will be Cyanide. The will probably have come across this substance watching World War II or James Bond movies. This aside, what do they really know about Cyanide?
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Cyanides contain the cyano group CN-. There is a triple bond between the carbon and nitrogen and the negative charge is centred on the carbon atom. In organic compounds the group is called a nitrile group.
Cyanide is toxic and it works by binding to Iron in an enzyme found in mitochondria. This effectively stops the mitochondria (and the cell producing energy) – if there is enough cyanide lots of cells cannot produce energy and this can have catastrophic effects if the cells effected are heart cells.
There is however an antidote cyanide poisoning – more on this tomorrow