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I'm actually quite surprised that this isn't really mentioned anywhere on the internet (or I'm just bad at searching)! Solubility in water is known to be directly related by multiple factors, and for organic molecules it's usually ability to form hydrogen bonds, polarity, bulk etc. I would imagine this trend would continue for most of the smaller alcohols (methanol, ethanol, isopropanol etc.) to some extent. However, I can't find even a brief mention on how solubility in common solvents is determined.

Let me share my (admittedly very elementary) logic: For a solvent like cyclohexane, which is non-polar, I imagine other non-polar solutes would be able to dissolve. However, if the non-polar compound is solid, it will require heating to break the van der Waals forces first. I assume little to no enthalpy change occurs in this process. Other more polar solutes would prefer to continue associating with themselves, and therefore not dissolve.

For a solvent like diethyl ether, it gets a tad more complicated. The oxygen atom on the ether is a hydrogen bond acceptor, and the molecule is polar. So, I imagine that non-polar solutes are poorly soluble. The same should go for compounds like amines, alcohols and carboxylic acids because they rather hydrogen bond with themselves. However, for meekly polar compounds with functional groups like aldehydes, ketones and halogenoalkanes, I imagine it depends on its polarity? It's polarity should be near that of the solvent; if it's more polar it will rather be with itself, if it's less polar the solvent would rather be with itself. So for example, if I mix ethyl chloride with diethyl ether, will they be miscible?

If anyone can support or debunk my logic, it will be greatly appreciated. miscibility chart

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  • $\begingroup$ There was a plethora of textbooks published from 1970s to early 1980s about chemistry happening in organic solvents. These books are good at delivering fundamental principles of intramolecular interactions and simple enough models for understanding basic principles of miscibility and selection of solvent for a particular synthesis. $\endgroup$
    – andselisk
    Feb 18 at 19:13
  • $\begingroup$ From the top of my head, I'd suggest 1. Nonaqueous Chemistry; Topics in Current Chemistry; Springer-Verlag: Berlin/Heidelberg, 1972; Vol. 27, and 2. Popovych, O.; Tomkins, R. P. T. Nonaqueous Solution Chemistry; Wiley: New York, 1981. Also, get to know Hansen solubility parameters. $\endgroup$
    – andselisk
    Feb 18 at 19:13
  • $\begingroup$ @andselisk Thanks! Will check it out. $\endgroup$
    – chematwork
    Feb 19 at 2:06
  • $\begingroup$ Not really clear what we shall confirm or debunk. Yes solubility is a huge topic with a simple principle (like likes like) and a lot of details. That is why polarity of a solvent is not, or is not necessarily its electrical dipole moment. . $\endgroup$
    – Alchimista
    Feb 19 at 11:26
  • $\begingroup$ @Alchimista I was just referring to the two examples I gave above (cyclohexane and diethyl ether), which can help me understand solubility as a whole ;) $\endgroup$
    – chematwork
    Feb 20 at 6:23

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