Question #88198

1 Answer
Aug 18, 2017

Well, simply because ethyl alcohol is not capable of separating ionic charges effectively.


Solvation of common salt requires the solvent to separate positive and negative and ions.....i.e.

#NaCl(s) stackrel(H_2O)rarrNa^+(aq) + Cl^(-)(aq)#

The aquated complex, what we write as #Na^+(aq)# is probably present in solution as the coordination complex #[Na(OH_2)_6]^+#. While ethyl alcohol has some polarity, and is certainly capable of hydrogen bonding, it is not as capable as water in charge separating, and solvating individual ions.

And here is an experiment you can try yourself. Dissolve some kitchen salt up in water (note that these days you can buy cooking salt for next to nothing), and then add some methylated spirit to the CLEAR solution. (Note metho is ethanol to which some methanol has been added to make it undrinkable!) You will see a cloudy mass of fine, white crystals deposit. What are the crystals?

Does sugar dissolve in metho? Why?