Why can covalent compounds dissolve in organic solvents? I researched about it a little and I found an article which said: "Mostly all organic compounds are non-polar in nature. Also, covalent compounds are by nature non-polar.". I'm not sure what it means for a compound to be "non-polar" or "polar" but I'm guessing it has something to do with net charge? Also, what does that have to do with covalent compounds being able to dissolve in organic solvents.

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    $\begingroup$ Really just a little. You should research more before asking, otherwise the question may be closed due duplicity and/or not enough of own effort. Polarity and solubility topics have been discussed many times on many places. The latter even in medieval alchemy ( similia similibus solvuntur ). $\endgroup$
    – Poutnik
    Aug 16 '21 at 9:28
  • $\begingroup$ There is one factor that is entropy. Itself, it provides a driving force. It can be not enough, so usually it is important the energetic of the molecules in their covalent solid vs that of the molecules surrounded by solvents one. Nothing is totally apolar. Organic solvents have various degrees of polarity too. So it is possible to find some balance. But to pose such a question you should read more on polarity of molecules or part of them. Once cleared, likely you won't even pose this question anymore. $\endgroup$
    – Alchimista
    Aug 17 '21 at 10:10

What an interesting way to ask about solubility!

Non-polar vs polar. We usually fret about relatively minor differences in solubility between polar compounds. Here, I'm going out on a limb and calling a factor of two minor.

But non-polar compounds are sometimes quite soluble in organic solvents: 10% or more, even in solvents where the idea of "like dissolves like" has no significance. That's quite a lot when you consider that some chemists are OK with calling a 1% solubility for an inorganic compound "somewhat soluble".

One way (not the only way, for sure) to explain the possible high solubility of non-polar compounds in organic solvents is to look at melting points: the organic compounds of greatest solubility are the ones with lowest melting points, i.e., lowest "lattice energy", if we may use that term, somewhere below 200C. On the other hand, polar inorganic compounds generally have melting points much higher - 500-600C or more (unless already hydrated), and only dissolve at all when their polarity is addressed by the solvent, e.g., water, with its hydrogen and/or oxygen bonding.

And although I dismissed "like dissolves like", "organic solvents" suggests non-polar, and the solutes were non-polar, so the solvent and solute did have some similarity, even if not by virtue of similar structures.


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