Studentsmi
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Solvent Tables
Does anybody know if tables are available that indicate the boiling points of different solvents under vacuum.
I know they exist at universities etc. But, I have not seen them elsewhere.
Rgds
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BromicAcid
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Solvent + Nomograph = Approx Boiling Point
At my university and my work we have nomographs posted on the wall for quick calculations of approximate boiling points, a bit more useful than
arbitrary pressures listed in many situations.
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peach
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Wikipedia lists the mains properties of common solvents in the tables of this article <----- click
There are also data pages for most chemicals on there which lists more detailed properties separately.
But bromic is correct with regards to the under vacuum part. You don't want a table for that, it's a nomograph or calculation.
There's one stuck behind the glass in the photo below. I printed one of the online ones and ran it through a laminator. The only downside to these is
that they all seem to be in torr and there aren't any nice printable ones with other common units on them, like mBar and Pascals. But converting from
torr to those isn't too hard, a torr is just over 1mBar. <---- here's a link to one you can print.
The nomograph stops at an atmospheric BP of 100C as most things below that don't need vacuum distillation.
This page has a calculator on it that's handy for things like that.
If you type 'nomograph' into google the first link will probably be the one on Sigma's page. If you already know the rough values, you can click away
on the nomograph to get an answer and be done with that.
But I'd highly recommend having a look at the tabs on the right of the window "pressure conversion", "temperature conversion" and "physical
properties". Physical properties is the one I find most useful, it's already loaded with information for most of what you'll be asking about.
If I scroll through the list and click "Dichloromethane" for example, all the properties and ranges appear in the data windows. If I type 2 degrees C
in the temperature box and click "Calc P", it gives me the pressure as 151.9 mmHg.
If I set the pressure as 50 mmHg and do the reverse, it tells me it'll be boiling at -19.8C.
It's be awesome if someone made a hand held calculator with all this jammed into it. I'll email Sigma. ;P
If you're feeling in the mood, you could plot a graph using the results from the sigma page at various pressures for a bunch of different solvents,
print and then laminate.
[Edited on 29-5-2011 by peach]
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The WiZard is In
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Quote: Originally posted by Studentsmi  | Does anybody know if tables are available that indicate the boiling points of different solvents under vacuum.
I know they exist at universities etc. But, I have not seen them elsewhere.
Rgds |
This has to be a day in-out common chemical engineering
question. I suffer from the though that you could fill a room
with charts/formulas.
Go forth onto the world and search for them.
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BromicAcid
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Peach, do you use the pressure equalizing arm of your addition funnel as a straight edge to read your nomograph? 
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ziqquratu
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There's also a flash-based version of that nomograph on Aldrich's website
http://www.sigmaaldrich.com/chemistry/solvents/learning-cent...
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peach
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She not be long enough... Arh!
I've emailed Sigma to ask them to make a (specifically red) scientific calculator with all of the more common things (molar masses, densities, vapour
pressures, BP's, constants etc) built in with nomographs and pH calculators. I suggested they make it USB compatible so it can be reflashed with new
firmware.
Lets see if it happens. It'll be killer if it appears, I'll buy one.
Failing that... a flash version for portable devices? My mobile was third hand and I don't even use it anyway, so I'd prefer the calculator
personally.
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