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Specialty Chemistry Forums => Biochemistry and Chemical Biology Forum => Topic started by: victer24 on August 26, 2014, 10:39:11 AM

Title: Potassium Cyanide salt life time
Post by: victer24 on August 26, 2014, 10:39:11 AM
Is there any life time for cyanide salt?

Which means after Three to four months, is that effectiveness of cyanide salt will reduce?
Title: Re: Potassium Cyanide salt life time
Post by: Borek on August 26, 2014, 02:05:06 PM
I believe on contact with air it can get oxidized (no idea to what) and less effective. That's what I was told many years ago by an entomologist using cyanide to kill insects.
Title: Re: Potassium Cyanide salt life time
Post by: Zyklonb on August 26, 2014, 02:24:53 PM
Hydrogen peroxide oxidizes cyanide to cyanate, so atmospheric oxygen may do the same.
Quote from Wikipedia:
Quote
KCN can be detoxified most efficiently with hydrogen peroxide or with a solution of sodium hypochlorite. Such solutions should be kept basic whenever possible so as to eliminate the possibility of generation of hydrogen cyanide:

KCN + H2O2 → KOCN + H2O
http://en.wikipedia.org/wiki/Potassium_cyanide#Toxicity (http://en.wikipedia.org/wiki/Potassium_cyanide#Toxicity)
Title: Re: Potassium Cyanide salt life time
Post by: Babcock_Hall on August 26, 2014, 04:43:58 PM
Oxidation sometimes uses a catalyst
http://www.sciencedirect.com/science/article/pii/S0304389404004546

Safe handling tips:
http://safety.chemistry.unimelb.edu.au/cyanide.php
Title: Re: Potassium Cyanide salt life time
Post by: snorkack on August 27, 2014, 03:25:13 AM
Can HCN be driven out by carbonic acid in air?
KCN+H2O+CO2=KHCO3+HCN?
Title: Re: Potassium Cyanide salt life time
Post by: discodermolide on August 27, 2014, 04:32:28 AM
Yes. But not in large quantities, enough to smell.
Title: Re: Potassium Cyanide salt life time
Post by: Borek on August 27, 2014, 06:58:23 AM
Yes. But not in large quantities, enough to smell.

If memory serves me well, HCN can't be smelled unless its concentration is way above the dangerous levels.

Sure, just because you can smell it above vial doesn't mean there is enough to kill you, still, if it can be smelled, it shouldn't be ignored.

Title: Re: Potassium Cyanide salt life time
Post by: discodermolide on August 27, 2014, 08:28:51 AM
I think it's like H2S, it saturates the nasal receptors and above a given concentration you can't smell it any more, but that may also be because you are dead!
Title: Re: Potassium Cyanide salt life time
Post by: victer24 on August 27, 2014, 08:42:27 AM
Thanks for your replies..

But your replies are suitable, when the potassium cyanide is kept in outside atmosphere.  (In this case also please let me know at what factor it will detoxified)

Lets say, if we place this salt in plastic closed container then what will be result after 4 to 6 months....

Thanks again..
Title: Re: Potassium Cyanide salt life time
Post by: discodermolide on August 27, 2014, 09:28:30 AM
No great change.
Title: Re: Potassium Cyanide salt life time
Post by: Babcock_Hall on August 27, 2014, 10:21:22 AM
"The smell of cyanide
Trained observers can detect 2 ppm HCN in air. The sense of smell fatigues easily and fails at higher concentrations. Some 20% of adults have a hereditary inability to detect the characteristic odour. Clearly the odour is not a reliable warning signal. Any odour of HCN in an open laboratory is a danger warning and indicates poor chemical technique."  (link previously given)
Title: Re: Potassium Cyanide salt life time
Post by: victer24 on August 28, 2014, 12:50:46 PM
No great change.

Can u please explain scientifically....?