ideletemyself
Member
I wouldn't really worry about that. Borosilicate glass in a laboratory setting is often referred to as "heavy wall" although sometimes it isn't listed but is still "heavy wall." In general I think it's safe to assume that most laboratory glassware if it's worth anything at all should be able to handle pressure changes even beyond what a simple vacuum can do as in experiments that are more involved with gases primarily. Also, they call the stuff high vacuum grease for a reason and if your set came with a vacuum adapter then the people making it should have ensured it could handle some fairly intense pressure changes. Maybe I'm assuming too much here in general but your glassware looks more professional than mine in my opinion and I wouldn't hesitate to attempt pressures beyond what my water aspirator can provide with my own glassware...Lol well I got plenty of shake sitting around just waiting to be used in these experiments so I'll be attempting to make the chloroform, and that's gonna be my first experiment.
Also I appreciate the heads up about the grease, but what I'm really worried about is if my rotary pump is too strong and if it has a chance of breaking the glassware when it reaches full vacuum, i know it's a kinda silly question but should I be using a hand pump?
If you mean a hand pump like one would use with a vacuum filtration set, then no way. While those can provide a vacuum, I can get mine all the way to -29hg when filtering other extracts, it's not the kind of vacuum that you'd want in a laboratory experiment beyond just for filtering. One thing that jumps right out at me would be the fact of that type of vacuum hand pump being used would create what is essentially a closed system. You want a way for the air to escape through the vacuum, continuously, if there is any. At least that's my understanding of it. Otherwise, there's potential of explosion through the buildup of gases. I seem to remember watching an old YouTube video from some college in Canada in the 80's, while it was pretty hilarious because of being from the 80's they made mention of not wanting to create a entirely closed system for that reason. I suppose you could attempt to use a hand pump as long as you had a multi-neck flask and used one neck with a gas-inlit with a glass rod spinner-thingy. That would also cut down on any bumping as well though you'll be using a magnetic stirrer anyways. I would just say that you'd have to be pretty fit to keep that vacuum going at a proper pressure continuously. I could be totally wrong about this but when dealing with explosions I try and keep those down to none and air on the side of caution. But I had thoughts of using the vacuum hand pump as well.
I'm curious, is there such an air bleed with your vacuum pump? Like does it seem as though the air would escape through the pump creating the vacuum? That would likely answer your question. If it does, then that means the hand pump is a no go but if it didn't if the air doesn't need to escape then I guess the hand pump would be valid. I have never seen or read anyone using the vacuum hand pump in such a situation which is why I assume what I assume. Hope that helped
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