Chemical Forums

General Forums => Generic Discussion => Topic started by: mike on September 01, 2006, 01:58:52 AM

Title: Hydrofluoric Acid
Post by: mike on September 01, 2006, 01:58:52 AM
What do people think? Is it appropriate to use HF in the undergraduate laboratory? The poll is probably a little black and white, I am sure there are a lot of "yes, but" and "no, if" answers.

I don't see how the benefits outweigh the risks here.
Title: Re: Hydrofluoric Acid
Post by: Mitch on September 01, 2006, 02:15:49 AM
I wouldn't think so, but if it's a low enough concentration and the appropriate safety precautions are taken it should be fine. It would be a good way to teach the students the proper reverence some chemicals deserve.
Title: Re: Hydrofluoric Acid
Post by: P on September 01, 2006, 05:58:44 AM
I wouldn't let undergrads play with it  -   maybe in the final year after a couple of lectures about how dangerous it is with some nasty, scary pictures of some industrial accidents? but I don't see the need.




Title: Re: Hydrofluoric Acid
Post by: AWK on September 01, 2006, 09:29:17 AM
Solutions of HF should be kept in teflon bottles, this solutions are a terrible lachrymator.
Title: Re: Hydrofluoric Acid
Post by: hmx9123 on September 01, 2006, 02:04:58 PM
My personal opinion is that HF should not be used for the masses; if you have a large university where you push 3500 students through general chemistry lab each semester (as my undergraduate university did), you will easily wind up with accidents.  If you have chem majors, a small select group, watched by graduate students who are into the course, it should be fine.  My school did this; chem majors did a couple labs that used HF, but they were in a much more controlled and supervised environment, and the solution was dilute.  It wasn't until we hit the undergrad/grad inorganic chemistry course that we used concentrated HF.  That being said, undergrads in engineering use that stuff all the time like it's water to etch silicon wafers, etc., and we don't hear of many problems with it.  All in all, though, I'd vote no.  It's a little hypocritical of me, because I think that most labs are watered down to the point where they're boring now a days.  For me, though, I do see a difference in a lab where something can catch on fire or give you a nasty topical burn as opposed to poison you.  For this reason, I wouldn't allow undergrads to work with dimethyl mercury or nicotine, either.
Title: Re: Hydrofluoric Acid
Post by: jdurg on September 24, 2006, 07:50:40 PM
I myself cannot come up with any reactions in which a much safer, and most of the time better, alternative to HF can not be found.  HF is needed for very specific types of reactions, and frankly an undergrad really has no reason to be working those reactions.  I mean in my undergrad work I did a lot of reactions involving horrifically toxic and dangerous chemicals, but that was because there was absolutely no other way around it.  In a toxicology lab you typically will work with nasty things like cyanides, uranyl nitrate, arsine, etc.  However, we were taught about the dangers and instructed on whether or not there were any better alternatives.  With HF, I just don't see any real reason to use it.
Title: Re: Hydrofluoric Acid
Post by: Bakegaku on September 30, 2006, 01:22:36 PM
Hmm... 4 people said it should.  I'm curious to hear their opinions on the matter.  I see Mitch's point, but I agree with jdurg and Mike among others in that the benefits don't outweigh the risks.
Title: Re: Hydrofluoric Acid
Post by: dfx- on November 02, 2006, 10:19:30 PM
Undergraduate and in final year myself and have never went anywhere near HF...

The only interaction we've had with HF are the faces that our lecturers pull when they mention it/it being used. ;D