How do we compare the degree of intermolecular force that operates in ethanol, to that which operates in glycerol, #"HOH"_2"CCH(OH)CH"_2"OH"#?
Clearly, glycerol, has a higher intermolecular force. There are several metrics we could use to determine this.
Compare the boiling point of ethyl alcohol,
All these data suggest that the intermolecular force that operates in glycerol should be much greater than that which operates in ethyl alcohol. The propensity of glycerol to hydrogen bond should be the determining factor. Why?