tino@hou2f.UUCP (A.TINO) (12/27/85)
An unopened bottle of salt-free seltzer, kept overnight in a sub-freezing room, remained liquid. I brought the bottle into a warm room and immediately removed the twist-off cap. Within seconds the liquid froze. Very dramatic! I can think of two contributing effects: 1) The increased pressure within the bottle suppressed the freezing point (as in regelation). When the pressure was released, the water froze. 2) The dissolved CO2 suppressed the freezing point. When the gas escaped, the water froze. I think the second effect is the more important one. Any comments? _______ Al Tino
mmm@weitek.UUCP (Mark Thorson) (12/29/85)
In article <601@hou2f.UUCP>, tino@hou2f.UUCP (A.TINO) writes: > An unopened bottle of salt-free seltzer, kept overnight in > a sub-freezing room, remained liquid. I brought the bottle > into a warm room and immediately removed the twist-off cap. > Within seconds the liquid froze. Very dramatic! > > I can think of two contributing effects: > 1) The increased pressure within the bottle suppressed the > freezing point (as in regelation). When the pressure was > released, the water froze. > 2) The dissolved CO2 suppressed the freezing point. When the > gas escaped, the water froze. > > I think the second effect is the more important one. > Any comments? > > _______ > Al Tino The bubbles of CO2 formed when you took the cap off provided nucleation centers for ice-crystal formation in the supercooled liquid. Mark Thorson (...!cae780!weitek!mmm)
larry@kitty.UUCP (Larry Lippman) (12/31/85)
> An unopened bottle of salt-free seltzer, kept overnight in > a sub-freezing room, remained liquid. I brought the bottle > into a warm room and immediately removed the twist-off cap. > Within seconds the liquid froze. Very dramatic! > > I can think of two contributing effects: > 1) The increased pressure within the bottle suppressed the > freezing point (as in regelation). When the pressure was > released, the water froze. > 2) The dissolved CO2 suppressed the freezing point. When the > gas escaped, the water froze. > > I think the second effect is the more important one. > Any comments? You got it - the reason is the presence of dissolved CO2 causing freezing point depression; the first reason is NOT a factor other than higher pressure causing more CO2 to remain in solution. The quantitative explanation for this phenomenon is expressed through Raoult's Law. ==> Larry Lippman @ Recognition Research Corp., Clarence, New York <== ==> UUCP {decvax|dual|rocksanne|rocksvax|watmath}!sunybcs!kitty!larry <== ==> VOICE 716/741-9185 {rice|shell}!baylor!/ <== ==> FAX 716/741-9635 {G1, G2, G3 modes} duke!ethos!/ <== ==> burl!gladys!/ <== ==> "Have you hugged your cat today?" ihnp4!/ <==
tan@ihlpg.UUCP (Bill Tanenbaum) (12/31/85)
> An unopened bottle of salt-free seltzer, kept overnight in > a sub-freezing room, remained liquid. I brought the bottle > into a warm room and immediately removed the twist-off cap. > Within seconds the liquid froze. Very dramatic! > > I can think of two contributing effects: > 1) The increased pressure within the bottle suppressed the > freezing point (as in regelation). When the pressure was > released, the water froze. > 2) The dissolved CO2 suppressed the freezing point. When the > gas escaped, the water froze. > > I think the second effect is the more important one. > Any comments? > _______ > Al Tino ----- I think (but am not certain) that neither effect is significant. Try 3) Supercooled liquid - Liquids can be cooled well below their freezing points without freezing if there are no imperfections present at which freezing can begin. When the pressure was released, the bubbles of CO2 were the "seeds" for ice crystal formation, i.e. freezing. -- Bill Tanenbaum - AT&T Bell Labs - Naperville IL ihnp4!ihlpg!tan
jp@lanl.ARPA (12/31/85)
I have seen the same phenomenon with a bottle of very cold soda pop. You open the cap, it makes a pffht sound (gas escaping) and proceeds to form ice crystals before your eyes.
pmk@prometheus.UUCP (Paul M Koloc) (01/01/86)
> > 1) The increased pressure within the bottle suppressed the > > freezing point (as in regelation). When the pressure was > > released, the water froze. > > 2) The dissolved CO2 suppressed the freezing point. When the > > gas escaped, the water froze. > > I think the second effect is the more important one. > > Al Tino > =>Larry Lippman @ Recognition Research Corp., Clarence, NY applauds: <= > You got it - the reason is the presence of dissolved CO2 causing > freezing point depression; the first reason is NOT a factor other than higher > pressure causing more CO2 to remain in solution. The quantitative explanation > for this phenomenon is expressed through Raoult's Law. > Bill Tanenbaum - AT&T Bell Labs - Naperville IL ihnp4!ihlpg!tan > Try 3) Supercooled liquid - Liquids can be cooled well below > their freezing points without freezing if there are no imperfections > present at which freezing can begin. When the pressure was released, > the bubbles of CO2 were the "seeds" for ice crystal formation, i.e. > freezing. You got almost all of it! Another contributing factor is: 4> the cooling (temperature drop) induced by the vaporization of the CO2 from the seltzer water. That is both the temperature of the fluid is lowered and the freezing point is raised. The collision point once reached proceeds catastrophically and precipitates further state changes. 5> The "ice crystal seeds" also work as places to facilitate the proliferation of "cavitation regions" for the "explosive boiling" of the CO2. This greatly enhances the rate at which the CO2 expelled, so much so that it contributes to the sudden opacity of the solid-fluid-gas mixture and sometimes causes such rapid expansion that the contents overflow and one might even feel a kind of bump if the container is being held in hand. As a kid I found opening near-freezing bottles of coke fun, and then sucking the slush out even "funner". I think that all 4 or 5? mechanisms contribute, not insignificantly! +---------------------------------------------------------+--------+ | Paul M. Koloc, President: (301) 445-1075 | FUSION | | Prometheus II, Ltd.; College Park, MD 20740-0222 | this | | {umcp-cs | seismo}!prometheus!pmk; pmk@prometheus.UUCP | decade | +---------------------------------------------------------+--------+
levy@ttrdc.UUCP (Daniel R. Levy) (01/04/86)
In article <1510@ihlpg.UUCP>, tan@ihlpg.UUCP (Bill Tanenbaum) writes: >> An unopened bottle of salt-free seltzer, kept overnight in >> a sub-freezing room, remained liquid. I brought the bottle >> into a warm room and immediately removed the twist-off cap. >> Within seconds the liquid froze. Very dramatic! >> >> 2) The dissolved CO2 suppressed the freezing point. When the >> gas escaped, the water froze. >> I think the second effect is the more important one. >> Any comments? >> Al Tino >----- >I think (but am not certain) that neither effect is significant. >Try 3) Supercooled liquid - Liquids can be cooled well below >their freezing points without freezing if there are no imperfections >present at which freezing can begin. When the pressure was released, >the bubbles of CO2 were the "seeds" for ice crystal formation, i.e. >freezing. >-- >Bill Tanenbaum - AT&T Bell Labs - Naperville IL ihnp4!ihlpg!tan Interesting. I have had the same thing happen with bottles of soft drinks that I have put in the freezer to chill quickly and forgotten just a little too long. There seems to only be a little ice in the bottle, then I pry off the cap--voila! lots of ice. If the supercooling theory were the reason, why was there a little ice in the bottle beforehand in my test? (Try it yourself, with something like Crush that comes in a clear bottle.) -- ------------------------------- Disclaimer: The views contained herein are | dan levy | yvel nad | my own and are not at all those of my em- | an engihacker @ | ployer or the administrator of any computer | at&t computer systems division | upon which I may hack. | skokie, illinois | -------------------------------- Path: ..!ihnp4!ttrdc!levy