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#1 Posted : 14 April 2008 09:36:00(UTC)
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Posted By Neil Pearson I was interested in the case of the litre bottle of nitric acid that exploded, injuring a lecturer. I checked through a few pages of threads but couldn't see anything on this. I was wondering what made the nitric acid become unstable. I assume there must have been some addition or impurity. The story says the guy was preparing "materials related to weld tests". Can anyone shed any light on this? If no-one happens to know about the specific incident, maybe someone who knows about welding might guess what the problem was? I'm just interested to ensure we don't have trouble with stored nitric acid ourselves. Here are some links to the story: http://news.bbc.co.uk/1/...land/bristol/7330656.stm http://www.ucu.org.uk/index.cfm?articleid=3196 http://nds.coi.gov.uk/Co...seID=364539&NewsAreaID=2
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#2 Posted : 14 April 2008 09:39:00(UTC)
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Posted By Neil Pearson Think I've just answered my own question. The BBC link was the last one I looked at and it says something different: it was a mixture of ethanol and nitric acid.
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#3 Posted : 14 April 2008 09:55:00(UTC)
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Posted By peter gotch Neil, Doesn't appear to be the first time this has happened. http://www.ab.ust.hk/sepo/tips/ls/ls005.htm Regards, Peter
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#4 Posted : 14 April 2008 10:05:00(UTC)
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Posted By Paul Leadbetter Neil See here: http://en.wikipedia.org/wiki/Nital Paul
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#5 Posted : 14 April 2008 10:16:00(UTC)
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Posted By Karen Todd I'll never forget the day in A-level chemistry when 2 teachers were trying to open a bottle of silicon tetrachloride and it exploded. They ran out of the room stripping off as they went, leaving us looking at each other as a white mist (hydrochloric acid fumes) filled the room. Thankfully we had the sense to leave immediately and close the door... K
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#6 Posted : 14 April 2008 12:11:00(UTC)
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Posted By Chris G Reminds me of the time when a collegue stuffed a frozen chicken with Sugar / Sodium chlorate weedkiller (with a fire inhibiter!)about 1lb in all & put it in the fireworks party bonfire. Part of the carcase broke a window 200 yards away. Good job we are all more responsible these days.
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#7 Posted : 14 April 2008 13:00:00(UTC)
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Posted By Smiff Was the chicken cooked?
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#8 Posted : 14 April 2008 14:17:00(UTC)
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Posted By Mike The second two website references are essentially correct. The BBC story, presumably unknowingly, is not quite correct. It was the bottle of conc. nitric acid that exploded, not the prepared nital etchant. It must be assumed that the nitric acid had become contaminated over time, but exactly how and with what will probably never be known.
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#9 Posted : 15 April 2008 08:11:00(UTC)
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Posted By Neil Pearson Thanks for the responses people. I remember a lab technician giving me a bottle of oleum instead of conc. sulphuric acid once. I started pouring it into a wet measuring cylinder, and the bang made me jump, so I basically threw most of the oleum over my clothes, which rapidly disappeared and I was left standing in my underpants. From Mike's response I'm still a bit mystified as to what exploded. How do you know the BBC report is wrong Mike?
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#10 Posted : 15 April 2008 10:26:00(UTC)
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Posted By Mike Neil, From the witness statement of the injured person. Sorry I am unable to comment further.
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#11 Posted : 15 April 2008 15:06:00(UTC)
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Posted By John Donaldson From the report its very difficult to know what went wrong. However when you consider that over 20 pages are devoted to Nitric Acid in Bretherick’s Handbook of Reactive Chemical Hazards it is not surprising that HSE took this case and were successful.
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