Steam - 7-4-2016 at 06:38
Hello, as project I am synthesizing a naphthalene based hydroxamic acid. I need to determine its pka's thus I was planing on doing a titration using a
gran plot. However, from research the compound is insoluble in pure water and needs an water/alcohol solution or a pure alcohol solution to dissolve.
My question is: what must I do differently when dealing with non-aqueous solvent and solvent mixtures when doing a titration.
Thanks in advanced for any help!
Bean - 7-4-2016 at 08:39
What indicator will you use ?
DraconicAcid - 7-4-2016 at 08:49
If it's only about 20% alcohol, you could probably treat it as a regular aqueous titration. If you put it in pure alcohol, it will have a different
Ka than in an aqueous solution.
Steam - 7-4-2016 at 21:08
Thank you! If it is a alcohol water solution is it possible to use potentiometric methods with a pH probe? I know the probes measure the hydrogen ion
activity but will the alcohol in solution mess that measurement up? Perhaps if it was calibrated in a alcohol/water/buffer solution?
^To Bean, I would rather use a potentiometic method if I could, obviously if I did use an indicator it would have to be soluble in the alcohol and
would have to have a pKa similar to the acid being analyzed. I believe the pKa of the compound is around 9.