Acuyo
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Does PH affect solubility of MeOH in H2O?
Would a shift away (either way, like a pinch of bicarb or a couple drops of HCL) from neutral have any bearing on the solubilty of methanol in water?
Asking under context of washing MeOH from DCM with DH2O, so another question is: if either of these would would work, would it affect the DCM?
Thanks
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DraconicAcid
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The pH won't affect it. The ionic strength would- the methanol will be more soluble in pure water than in a solution with a high concentration of
ions. But a couple drops of HCl isn't going to affect it.
And dichloromethane will not react readily with either acid or base.
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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Acuyo
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edit: NVM, I read it backwards.
So basically, distilled water is probably my best bet
thanks
[Edited on 24-10-2016 by Acuyo]
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AJKOER
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Theoretically, pH should not have any significant impact.
That being said, in the presence of an alcohol water mix, where the latter is the likes of tap water containing dissolved oxygen and potentially rich
in transition metals (like Fe, Mn, Cu from plumbing, or trace amounts of Co....) in practice with time, I would not be too dogmatic on the potential
for no impact.
Just add an acid source presence in air (required with Fe, but not so much for Cu or Co salts, for example) and dissolved oxygen with a good amount of
time, one may be able to start via metal autoxidation, a Fenton or Fenton-type reaction chain, for example (see reactions R1, R4 and R5, in the case
of iron, available online at https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2626252/ ) especially in the presence of light. The latter chain introduces hydroxyl radicals and
hydroxyl ions (which would raise pH, at least at one point in time). Some of the CH3OH could be eventually broken down into CO2 and water.
To be complete, starting with, for example, a transition metal salt of Cobalt and an oxygen source, in the presence of H2S (see discussion and cited
reaction sequence at https://www.sciencemadness.org/whisper/viewthread.php?tid=70... ) or SO2 leading to HSO5- (see discussion, sources and presented reaction with
links at https://www.sciencemadness.org/whisper/viewthread.php?tid=67... ), then one can have a parallel sulfate radical system to Fenton (see, for
example, "Effects of chloride ion on degradation of Acid Orange 7 by sulfate radical-based advanced oxidation process: Implications for formation of
chlorinated aromatic compounds" by Ruixia Yuan, et al, DOI:10.1016/j.jhazmat.2011.09.007, available at https://www.google.com/url?q=http://scholar.google.com/schol... )
[Edited on 29-10-2016 by AJKOER]
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