At 12:33 am ((PST)) Sun Jan 28, 2007, Stefan Trethan wrote:
>On Sun, 28 Jan 2007 09:01:40 +0100, Randy Ledyard wrote:
> > How many other compounds are there out there that smell like rotten eggs?
> > Thiols/Mercaptans/Sulfides are the only ones I know of...
>
>If a comment from a neighbour would suffice to identify chemicals
>that would make for a cheap analyzer ;-)
Some groups of chemicals are easily identified by smell, for example,
ketones or esters. Most common plastics can be identified by
cautiously sniffing their combustion products. It is a commonplace
to choose between various palatable or tainted foodstuffs by
agreeable or disagreeable smells. The nose can be a quite
discriminating analytical instrument.
Sulphurous compounds can be uniquely recognizable and
disagreeable, especially, but not limited to, those that are
produced by rotting meat (and in my unfortunate experience,
rotting onions).
You may be relying on your or your neighbour's ability to detect
ethanethiol at a concentration as low as one part in 2.8 billion
to protect you from an explosion from a natural gas leak: see
http://en.wikipedia.org/wiki/New_London_School_explosion[If you've been at the ammonia bottle again, you're excused ;-) ]