[jubba]

Ethanol dissolves polar substances because it is polar
But why does it dissolve non-polar substance?
I know that the hydrocarbon chain can form dispersion forces but is there any further theory behind this.

[RyanJones]

I understand why polar sounstances are dissolved in a polar solvant but I'm interested to know why non-polar substances dissolve at all :S

Cheers,

Ryan Jones

[jwesterway]

Remember the old rule? Like dissolves like?
Ethanol has both a polar (-OH) group and a non-polar (CH3-CH2) group. Hence it can participate as both a polar and non-polar solvent.

-Josh

[Yggdrasil]

Polar and non-polar is not an all-or-nothing kind of thing.  There are different degrees of polarity.  Ethanol is a moderately polar solvent compared to water.  It can disolve many polar compounds, but it has trouble disolving very polar compounds like ionic salts.  Similarly, it can disolve slightly non-polar substances (like carboxylic acids), but it cannot disolve molecules which are strongly hydrophobic (like hydrocarbons).