Order of elutants and polarity [Column Chromatography]

[Xo1991]

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Referring to Destroyer #77 in the 2013 version.

Destroyer mentions that as polarity in a molecule increases, it'll take longer to get through a column chromatography. makes sense.

But can anyone provide reasoning on how alcohols are more polar than ketones. and how are ketones more polar than an ester, which has two oxygens?

Thanks.

 

[Ferneezy]

alcohols can form h-bonds: highly polar

ketones, via resonance and electronegativity, are polar (partial negative charge on O, partial positive on carbonyl C) however not as much as an h-bond

esters are functionally similar to ketones, but the C-O bond dipoles are about 120 degrees apart. that virtually cancels out the net dipole moment of the functional group.