Scratch- - 8-3-2005 at 07:12
I feel kinda stupid for not knowing this, since its alredy been (Attempted) explained to me. I usually get these things right away, but I dont
understand reflux. According to the guy I talked to reflux is when you condense the vapors of a reaction and put them back in the reaction vessel.
1) What exactly does refluxing something do?
2) The guy I talked to said he used it to get an oil from red peppers (capsacin?), how exactly if he is putting all his condensed vapors back in the
reaction (The answer to the first question will probably answer this)?
3) Is reflux related in any way to acid reflux (Referring to your stomach)?
sparkgap - 8-3-2005 at 07:47
The book by Zubrick uploaded by S. C. Wack (see here) has a nice explanation on the ups and downs of reflux. Suffice it for me to say that reflux is merely a method of getting two or more
reagents to react with the influence of constant heat. 
To answer your second question, in a reflux setup, there is (or should be) a condenser neatly placed on top of whatever flask you are doing your
reflux in. (You WILL be doing your reflux in a proper flask, yes?) Now, since the condenser is at a cooler temperature than your flask (condensers are
usually cooled with ice water), any raving-to get-out vapors emanating from your flask settle nicely on the condenser, and the resulting drops just
roll back docilely into the flask. And the cycle continues thus...
On the third question, only slightly related. The proper medical term is gastroesophageal reflux disease, or GERD. In this unfortunate malady, HCl
tends to escape the clutches of the lower esophageal sphincter muscle in a marked defiance of peristalsis, thus bathing your esophagus in a nice
stream of pH ~2 glop. 
Most common when in supine position... The reflux part
is because it goes up when it's supposed to be staying deep down.
sparky (^_^)
Scratch- - 8-3-2005 at 10:42
Ah, interesting book. Yes I have a proper flask, but not a proper condenser (They cost lots of $$). I would rather make a condenser, it seems like a
cooled copper pipe or vinyl tubing would make a nice condenser for refluxing. Is refluxing used much in inorganic chemistry? I dont have much
experience with organic chemistry.
Kanem - 8-3-2005 at 13:54
I know thar it is used to make certain esters, because they and the components they are made from are rather volatile. And you have to heat them if
you want to get a reaction.
Without reflux, you'd have not much of anything left after the reaction, not to mention that the stuff would only react partially.
Kanem
unionised - 10-3-2005 at 13:57
In chemistry and medicine the word means "to flow back".
It's very popular on organic chemistry since it lets you keep something at constant temperature for ages very easily and cheaply. I'ts
rather less popular in the gut.
sparkgap - 11-3-2005 at 07:02
Using vinyl pipe/tubing looks good to me, but the copper pipe, I don't know. I'm fearing the verdigris in the copper might leach into
whatever you're refluxing, that is, unless your copper tubing is new and shiny.
sparky (^_^)
Scratch- - 11-3-2005 at 07:24
I can easily get some more vinyl tubing at a local hardware store.
unionised - 13-3-2005 at 03:00
Most flexible vinyl tubing has a lot of plasticiser in it. This will leach out into your reaction mixture and make a mess of things.
Clean copper would work perfectly well (and has done for years as the stills used for making whisky show).