11/30/2006

Pink?

In the spirit of Jokerine's blog (which rocks, by the way, and you should read it)[1]...today I will show you some lab equipment for non-chemists. This is a rotovap. It is a wonderful but sometimes maddeningly slow invention.

[Non-chemists: The rotovap is used to remove solvent. Place "stuff in flask" in flask and stick onto bump trap. Be sure to clip, or flask may fall into water bath, causing much agony and cursing. Turn on vacuum and set the rotovap to rotate the flask. Turn on water bath to heat things up if needed.]

The oddity in this picture, and the reason I am posting about this at all, is that the stuff in the solvent trap is pink. For those who are unfamiliar with common organic solvents, none are pink. No bumping (excessive bubbling of "stuff in flask") has occurred. So why the pretty color?
Sometimes the "stuff in flask" contains something volatile that can end up in the solvent trap. An unfortunate example of this is bromine. If the solvent trap turns reddish-brownish-orangey, and especially if your eyes start burning (which may happen if rotovap is not in hood), you've got bromine. Doesn't seem to sting as badly if you were using NBS as opposed to Br2 --but my experience is limited.
However, the stuff in the solvent trap in the picture is pink, not orangey. Most likely it's iodine.

[1] Another blog that does the same thing on occasion is She Blinded Me with Science. It, too, rocks and you should read it. But it wouldn't fit into the sentence. Non-chemists, take note.

7 comments:

Excimer said...

I'm fairly certain bromine is Satan's chemical. Few (commonly used) chemicals can wreak so much havoc on your system quite like bromine can.

Jokerine said...

Really? I was thinking of using HBr in a Blanc reaction because it is a better leaving group than Cl and I could easilly do substitution on a moecule which is surprisingly inert.

Anyway I usually don't use rotovaps. My vakuum line has so much more power!

Mike said...

I didn't know you're fluent in German, Ψ*Ψ. What a small world.

Ψ*Ψ said...

I don't speak a word of German, mike. If it is chemistry-German I can read some of it because about every third word is the same as English.

Mike said...

Oh, well I realised afterwards, that the blog is written bilingual. Keep on trying ;-)

MaynOne said...

Cool gizmo. Now, the booze comes out where?

Carmen Drahl said...

Thanks for the shout-out. The rot.evap. is a great instrument to show non-chemists, as it incorporates bubbling, spinning, and dripping all in one glorious package. Now, if only my lab had a Jacob's ladder.