This is one that will be familiar to anyone who works in chemistry, but I was a bit surprised to see it the first time I went into a lab.
Certain compounds, called esters, can be prepared from an acid and an alcohol (usually a carboxylic acid). They are ubiquitous in the flavor and fragrance industry (although they’re not quite stable to water over the long-term, and once an ester is hydrolyzed, it liberates its component alcohol and acid, which are often pretty rank).
One classic organic lab is preparing some sweet-smelling esters from otherwise nasty-smelling carboxylic acids and esters (such as, for example, amyl butyrate, prepared from pentanol and butyric acid, the latter of which smells of vomit). So, with all this, I always just thought of small molecule esters as slightly unstable, nice-smelling things you usually encountered in small quantities.
I was surprised to see a giant 4-liter jug of ethyl acetate the first time I worked in an organic synthesis lab. Like most esters, it has a nice smell, although this one isn’t quite as sweet as other esters. Apparently it’s used as a fruit flavoring occasionally, but it finds most of its use as a solvent (non-acetone nail polish remover usually mostly EtOAc, for example).
Ethyl acetate is one of the few bulk esters you’ll encounter – probably because ethanol and acetic acid are so ubiquitous and cheap. The only other I can think of off the top of my head is propylene carbonate. You used to see people use butyrolactone (GBL) a lot – I’m told it’s tops as far as solvents go – but being a precursor to GHB, legitimate use decreased sharply a few years back. Apparently you can still buy it, but I’m sure it’s one of those “watched” chemicals.
Esters – gotta love ’em.