Steam
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Non-aqueous titration
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!
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Bean
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What indicator will you use ?
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DraconicAcid
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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.
Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
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Steam
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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.
DISCLAIMER: The information in this post is provided for general informational purposes only and may not reflect the current law in your jurisdiction.
No information contained in this post should be construed as legal advice from the individual author, nor is it intended to be a substitute for legal
counsel on any subject matter. No reader of this post should act or refrain from acting on the basis of any information included in, or accessible
through, this post without seeking the appropriate legal or other professional advice on the particular facts and circumstances at issue from a lawyer
licensed in the recipient’s state, country or other appropriate licensing jurisdiction.
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