Your question is definitely a tough one. I like
your thinking and feel that you have a reasonable
argument, but of course this isn't one of those
'ideal' situations that we often wish we were in.
Examining your situation, my first instinct was
that the difference in air temperature would be
too small to see such a noticeable effect. Then I
started thinking about the diet coke I had today
at lunch. After having the soda in my glass, I
added some ice and saw more foam. This didn't
make sense at first since the solubility of gases
is usually higher at lower temperatures. However,
the carbon dioxide of soda is forced in creating a
super saturated solution. So, how does the ice
speedup the liberation of carbon dioxide? My next
guess would be the vapor pressure- or the drop of
pressure that you eluded to in your question. To
test the temperature reasoning, you can perform an
experiment with different temperature glasses and
measuring the volume of foam that forms.
our case is not ideal I thought up some factors
that may also effect how and why the foam forms.
It may be possible that the thin layer of frost on
the glass creates a rough surface for the foam to
cling giving the build up of foam an appearance of
being more than just the invisible gas escaping
near a smoother surface where it wouldn't cling.
The viscocity of the liquid could control the foam
rate. The way the liquid is poured into the glass
may have an effect on the foaming. And looking up
some information about beer I found that lighter
beers almost always have less foam than darker
beers because of the hops that are used in production.
Click Here to return to the search form.