Sciencemadness Discussion Board

Chemistry Material

PainKilla - 13-11-2004 at 17:32

Hello all,

It's almost Christmas (or Hanakah, pardon spelling) but more importantly buy-buy-buy and gifts time :). I have a big list of chemistry related stuff but need a defined list of what to get...what would be a good glassware etc to get?

As of now, stuff I am defeitnly getting are a:
Distillation Set

Big list huh? I have thermometers that are -20C to +150C, with nice sized increments. Some glassware (not much at all, since it breaks so quickly :p) and that's it lol. I also have a scale but I'm going to get one that measures in milligrams soon. BTW, can someone can explain the whole Bomex, Pyrex, etc...I have no idea what they all do, or which one is best. I currently have Borosil.

Chemicals are useful too, but I am not quite sure what to get of those chemicals... I am getting more involved in organic chemistry, though I have a while (never :/ ?) until i fully understand it. So what are some good chemicals to get too? One that make solvents are useful too :). Not many though I am sure, dioxane IIRC was made easily though. Thanks for your replies.

[Edited on 14-11-2004 by PainKilla]

The_Davster - 13-11-2004 at 19:02

Just a few ideas, of course what you need depends on what areas of chemistry you want to get into, so for now I will just list a few essentials. The only chemicals I am listing are ones that you will most likely need for anything in chemistry.
-->Hotplate/magnetic stirrer (works well with your distillation equipment)
--> Basic Acids; conc. sulfuric, nitric, hydrochloric and maybe even phosphoric
-->Basic Bases; NaOH, KOH
-->Solvents; MeOH, EtOH, isopropyl, acetone, distilled water
-->How about a stand and clamps for your distilling apparatus? Or vaccum adaptor and aspirator

As for your glassware question, the best glassware is Schott/duran, the worst is anything that is not borosilicate. Pyrex/Kimax is good quality, not as great as Schott/Duran, but still quite good. Personally, I dislike Bomex, it cannot withstand thermal shock as well as pyrex/Kimax, the only glassware I have broken happens to be Bomex (not including glass rod for stirring).

neutrino - 13-11-2004 at 20:25

From what I have gathered and personal experience:
Duran/Scott = extremely high quality glass
Simax ,Pyrex/Kimax= very high quality glass
Borosil = decent Indian glass
Bomex = cheap Chinese glass of questionable quality

For a distillation setup, go Here. And get a Distillation distilling kit (the exact name escapes me) with Buy It Now, it will set you back ~$155. You will receive a brand new vacuum distillation kit with free shipping. :D I recommend getting another flask for boiling, though, as heat conduction through heavy-walled glassware is not too fast. For holding the thing up, you will need 2 stands and 4 buret clamps.

edit:
Shouldn't this be in the Reagents and Apparatus Acquistion forum?

[Edited on 14-11-2004 by neutrino]

PainKilla - 14-11-2004 at 10:58

Thanks for your replies so far. I am not sure which forum this would go in, since it's not really hard-to-get material. I "WISH" the mentioned chems, though they are of not the best quaility. HCl 20% :/ h2so4 rooto, red devil lye, some polyols ;), urea, AN, sulphur, Al, acetone, IPrOH, lots of h2o2 30%, a certain liquid metal ;), and an element under Bromine, above astanstine or w/e it is.... and no I don't plan on making drugs at all, at least not illegal ones.

About distilled water, would a regular still that is very clean be able to make relatively well distilled water? The real ones are quite expensive....

[Edited on 14-11-2004 by PainKilla]

neutrino - 14-11-2004 at 13:29

Normal distilled water from the supermarket should work fine unless you need some high quality. What is IPrOH? Isopropanol, i.e. isopropyl alcohol, i.e. rubbing alcohol?

rift valley - 14-11-2004 at 13:46

Thats funny, I am also getting a glass distilling rig from UGT for xmas. Since water aspirators are out of the question I am think about asking for a vacuum pump for my birthday. What do you guys think of a pump like this http://www.cynmar.com/product_info.php?cPath=122_257&pro... Since I don't know much on the subject can anyone point me towards some good info on vacuum pumps for home experiment use?

garage chemist - 14-11-2004 at 13:50

rift valley- why are water aspirators out of the question? I have one and it works great, it lowers the boiling point of water to about 28°C. Now you can calculate the vacuum it makes.

Oxydro - 14-11-2004 at 13:54

I would say that The Bell Jar is probably the best resource to find out about vaccuum pumps.

S.C. Wack - 14-11-2004 at 14:22

Given that the product does not have its vacuum mentioned on the site, buying it would be throwing your money away, just like paying $255 for that glassware collection.

With a pressure of 60 psi, the vacuum probably isn't very strong. For the same price (includes shipping) you could get one (rotary-vane, though) that pulls down to 50 microns.

Old refrigerator compressors have been mentioned before I'm sure. Tecumseh, Chrysler, and Copeland made very good compressors.

PainKilla - 14-11-2004 at 14:35

IPrOH is indeed isopropanol...I didn't know you could get distilled at the super market! Hmm. I think I trip to the super market for food and chemicals is in order, I hope buying foods and chemicals won't seem strange :). BTW, how exactly do vacuum's in labs work. I know they would be used to lower boiling points and help sperate stuff. What else can they be used for? And are they worth getting? I ahve around a 300 dollar or so budget. U.S. dollars that is

neutrino - 14-11-2004 at 19:25

The main problem with vacuum pumps is that they require traps to keep chemical vapors out of them. As for aspirators, there are different kinds: those that are designed for filtration suction (low vacuum) and those for creating an actual vacuum. The latter can be found on eBay for ~$25.

Magpie - 16-11-2004 at 12:15

I have used aspirators run off sink faucets many times and agree that a decent vacuum (~25-30 mmHg absolute) can be achieved with cold water at good pressure with a good (non-fouled/worn) aspirator.

Recently I had my first experience using a vacuum pump. This was to supply the vacuum needed for a vacuum distillation of methyl salicylate (oil of wintergreen). A vacuum of <50 mmHg absolute was specified. As my aspirator was fouled/worn this could not be used. So a vacuum pump was used. The manometer on the vacuum pump system indicated 40 mmHg absolute. However, the wintergreen boiled at 106 deg C, which according to a BP/pressure nomograph (based on the Clausius-Claeyron equation) the true vacuum was more like 20 mmHg absolute. So the pump did the job nicely. But as previously mentioned a cold-finger trap inserted in a dewar with dry ice/acetone was required to condense out nasty vapors to prevent them from entering the vacuum pump.

The vacuum pump system is tedius because of the trap requirement. So I agree that for situations where the vacuum needed is not more than 25-30 mmHg absolute an aspirator would have been much easier to use.

Lab acquistions

MadHatter - 16-11-2004 at 13:12

I have a mixture of glass types in my lab. I use the Bomex stuff for mixing although I have
boiled materials in it. In 1 case an 800 ml beaker developed a hairline crack while
crystallizing KClO4. Some of my erlenmeyer flasks are Bomex and I restrict their use to
mixing. All of the filtration flasks are heavy-walled Pyrex or Kimax. Necessary for vacuum
applications.

As for actual vacuum, I agree with Magpie that a hydroaspirator works great for most
applications and I find them particulary useful for vacuum distillation of acids. They
have the advantage in that the really nasty fumes get washed down the drain. I'll save
the rotary vane pump for air-conditioning work. It easily pulls over 29" inches of
mercury. I use the hand-held vacuum pump with the filtration flasks. Look in an auto
parts supply store for those.

Magpie, what model/type of vacuum pump do you have ? Mine is a Pneumotive model,
TA-0040-V rotary vane pump. The specs. on the face plate indicate it pulls 26" but I've
measured over 29". Maybe the manufacturers understate this to guarantee a
minimum pull. My EPA 609 automotive air-conditioning license requires 28" for freon
recycling tanks so I'm in good shape.

Magpie - 19-11-2004 at 14:58

Mad Hatter,

I don't own a vacuum pump. The one I used belongs to my school. They have several around, i.e., an Edwards and a Gast among them. I really don't know anything about their construction or performance specifications. I'm just beginning to learn about them.

Ref: Chemistry Equipment for Christmas

solo - 19-11-2004 at 15:22

Well once you have your distilling set , get a good scale , a rotovap, and just to feel good get a Hydrogenator.

This will keep you busy for many hours making your dreams come trough........solo