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Is it possible to put a substance with low volatility into a highly volatile solvent, thus make the original substance also vaporize quickly?

If not, are there anyway to increase it's volatility?

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The important thing is the solvent does not dissolve the substance. Then their vapour pressures sum up and they boil together.

This technique is massively used for obtaining aromatic oily essences from plants, that are mostly insoluble in water.

The destilate usually forms a stable emulsion, that gets extracted by lipophilic volatile solvent, that is later evaporated to got the substance, or a mixture of them.

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  • $\begingroup$ Actually any positive azeotrope (with a Bp. minimum) works. E.g. adding ethanol makes it easier to evaporate water. $\endgroup$
    – Karl
    Dec 23, 2019 at 14:11
  • $\begingroup$ @Karl Hmm, but azeotropes are hard to find and even them decrease the vapour pressure of the less volatile liquid. $\endgroup$
    – Poutnik
    Dec 23, 2019 at 14:16
  • $\begingroup$ Basically any two substances with different polarity form an azeotrope. What you propose is also one. en.wikipedia.org/wiki/… $\endgroup$
    – Karl
    Dec 23, 2019 at 14:35
  • $\begingroup$ Methanol does not form an azeotrope with water. For existence of an azeotrope, the deviation from Raoult law is not enough. It must be high enough deviation. Neither nonmiscible liquids form azeotropes. Each maintains its vapour pressure like the other was not present. $\endgroup$
    – Poutnik
    Dec 23, 2019 at 14:47

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