Hey, chemists!

[swan_tower]

How would you describe the smell of acid? Does it have a smell? (Any kind of acid will do; I'm looking for commonalities here.)

Comments

[cepetit.myopenid.com (from livejournal.com)]

Perhaps the German name for acids will help, a little bit:
sauerstoff
(literally, "sourish stuff").

Most of smell relates not to the classifying chemical nature of a compound, but to the remainder of the compound and impurities (natural or otherwise). For example, the particular "smell" of sulphuric acid wafting through most laboratories is usually the smell of ionized impurities, decayed glassware and tubing, and the occasional metallic bits that have vaporized. More to the point, to a less-than-highly-trained nose there's almost no odor difference between excruciatingly pure ethanol and excruciatingly pure acetic acid... but in their natural states, there's an obvious difference between store-bought "grain alcohol" and store-bought distilled white vinegar, even if both are allowed to sit in identical containers for a few hours to let container odors boil off.

As an aside, this was one of the primary problems with both pre-electrical chemistry and alchemy: Impure reagents made figuring out what was going on virtually impossible. One of the less-obvious accomplishments of the German organic chemists of the 1830s and 1840s was their imposition of "clean lab" practices as the default, which in turn gave them a substantial advantage for non-vapor-phase chemistry over their French and English counterparts for about twenty years... much to their dismay when advanced German chemistry using purified picric acid led to better munitions in time for the Austro-Prussian and Franco-Prussian Wars.