Ask A Scientist General Science Archive

name         Michael W.
status       student
age          10

Question -   Which is more hygroscopic, honey or sugar? And why?
------------------------------------------------
In a list of hygroscopic substances neither would rank very high compared
to many other substances; however, I would think that sugar is more
hygroscopic because the surface area exposed to atmospheric moisture is so
much larger that of honey.

Vince Calder
========================================================
Dear Mike:

Hygroscopicity is defined as "absorbing moisture (as from the air)".
Although not an exclusive property of solids, they typically do absorb
moisture much more readily in their pure form than in aqueous solution.
Therefore, sugar, in its solid state, absorbs moisture more readily than
honey, which is essentially sugar that is already in an aqueous solution,
albeit a very dense, concentrated one.  Thus, sugar is undoubtedly more
hygroscopic than honey.

I hope that this helps to answer your question,

Jeff Buzby, Ph.D.
=========================================================