The Vespiary

The Hive => Chemistry Discourse => Topic started by: lastchance on September 11, 2004, 10:59:00 PM

Title: soluability of ethyl bromide in dmso
Post by: lastchance on September 11, 2004, 10:59:00 PM

Simple question...  Whats is the soluability of ethyl bromide in DMSO vs DMF?

Title: I'd say that they are fully miscible.
Post by: Rhodium on September 12, 2004, 07:02:00 AM

I'd say that they are fully miscible.

Title: is there any rule of thumb relating dielectric
Post by: stratosphere on September 12, 2004, 08:01:00 AM

is there any rule of thumb relating dielectric constants of a solvent+intended solute  to the solubility of the intended solute in that solvent?

for instance lets say the dielectric of a solvent X was 30, and the dielectric of solute Y was 5, can we take those number and get an estimation of the solubility of Y in X?

Title: after looking at a bunch of examples heres the
Post by: stratosphere on September 12, 2004, 08:42:00 AM

after looking at a bunch of examples heres the rule of thumb i came up with, like all rules of thumb it is not exact and one would not have to work real hard to find exceptions.
but if you take the ratio of the dielectric constants, putting the biggest one in the numerator.

if the number is less then 4 they will be miscible or nearly miscible.
if it is between 4 and 7 they will be somewhat soluable.
if it is greater then 7 they will be insoluable.


given that the dielectric for bromoethane is about 10, and that for dmso and dmf is 47 and 38 respectivly, we'd expect  EtBr to have a fairly good solubilty in either one, with dmf probobly being the better one.