SureTrack Users General Discussion

[Dr.Jake]

HE DID THAT THIS MORNING BEFORE WERK. Bout time to go home now and make adjustments.......hehehehe

[Dr.Jake]

This ain't not too un-stupid eh? Never noticed all the extra monkey business in that last scene.
You spray moar, ya git moar.

[greasybob]

Dr.D , did you give a donation to the Venetian Blind when you were there ? It's 2015 now, that means the it's been a good 7 years since TPMS was made mandatory. The batteries are running out ( 7 year life expectancy), if the aluminum sensors haven't all rotted away already. When they start coming in with the TPMS light on what are you going to do ? Recommend they all get replaced right away ? If you only replace one because the battery died and the light comes back on next week because the next one died, will you look incompetent ? Costumers only know lights, they're not much on reasoning. Finally came up for some air after the polar plunge, refreshing !!!!!

[Dr.Jake]

Looks like that ice water would be a shock to your carcass. I think that women's mudflaps fell down. hehehehe
Greasy ya look healthy and young. I was thinking you a old turd like me.

Hope you warmed back up by now. It wood take me a week to quit shivering.

[greasybob]

10 below today for a high. a good to time for a science experiment, Your MT Dew looks normal till you open it, then turns to ice, Why ?

[maven]

10 below today for a high. a good to time for a science experiment, Your MT Dew looks normal till you open it, then turns to ice, Why ?

The pressure drop from opening the cap allows the dissolved CO2 to transition from liquid to gas, as this occurs it rapidly cools the soda, freezing it.

[Crusty]

The pressure drop from opening the cap allows the dissolved CO2 to transition from liquid to gas, as this occurs it rapidly cools the soda, freezing it.

LOL....Air Conditioning 101.....change in pressure = change in state, and vice versa.....As the CO2 changes from liquid to vapour, it takes BTU's with it thus cooling the Dew.....Happens with my Honey Brown when it's below freezing in the bottle. Today's not a good day to experiment though... It'd be a waste....LMAO

[greasybob]

Hmmm... and I thought it was a pressure thing, the Dew is under pressure lowering the freezing point, release the pressure and the super cooled Dew freezes.. Gotta get my temp gun and test this out. Interesting though that the Dew slushie starts at the top and freezes it's way down. If pressure raises the boiling point does it lower the freezing point ? I should have mentioned that the dew was below the freezing point when opened. If it gets cold enough tonight I,m going to try the boiling water trick to see if it crystalizes

[chaskuss]

Answer: All of the Above

Actually, I believe that you are both correct. It is a combination of the drop in absolute pressure inside the can, and the change in state of the CO2.
Charlie

[Nick_Taylor]

You can do the same thing with regular bottled water. If you lay it on its side in the freezer and then carefully take it out a couple days later and then squeeze it or thump it, it will "freeze" from the top down. You don't have to open it.

Here's a video showing it - http://youtu.be/25SHX5Sj7ZA

[Crusty]

Hmmm... and I thought it was a pressure thing, the Dew is under pressure lowering the freezing point, release the pressure and the super cooled Dew freezes.. Gotta get my temp gun and test this out. Interesting though that the Dew slushie starts at the top and freezes it's way down. If pressure raises the boiling point does it lower the freezing point ? I should have mentioned that the dew was below the freezing point when opened. If it gets cold enough tonight I,m going to try the boiling water trick to see if it crystalizes

It takes one BTU to change 1-LB of ice into water, and it takes one BTU to change one -LB of water into steam.
Conversly it gives off one BTU to change one -LB of steam to water and it gives off one BTU to change one -LB of water into ice.....

Now if you change the pressure to change the state of a liquid into a vapour, or use pressure to change the state of a vapour into liquid, it's that change of state that takes BTU's..... Air conditioning 101, or rather BEER cooling 101.....LOL

Smaking a bottle of anything puts energy into it, and can release molecules from a condensed state into a vapour and thus the BTU exchange happens.

[chaskuss]

Now I understand

snipped or rather BEER cooling 101.....LOL
snipped

Crusty, thanks for putting this into terms I can relate to!

Charlie

[liljoe]

At 4 degrees this morning, I found it rather difficult to get the old Kaw to fire off and the throttle was frozen making it stay in what ever position I put it in. One good thing; instant cruise control!!!

Hope all are busy and warm....

I did bust the ice in the pool and it is about six inches thick and rather hard to break with a 5 lb hammer.

[maven]

The reason bottled water, or even a glass of water freezes instantly when you pick it up is because the water was slowly cooled below its freezing point but there was no nucleation site for crystals to form, the motion created the nucleation point and allowed a crystal to form causing the reaction.

As far as pressure reducing the freezing point of water, while it does occur its not a significant function in this reaction as one might expect. Pressure has a relatively minimal affect on freezing point. Heres a table showing the phase states and changes of water at pressure vs. temperature.

The capital "E" is average conditions here on Earth the vertical line the left of that E represents the temperature/pressure relationship at which the liquid/solid change occurs, follow that line and youll see theres negligible real world difference in freeze point from 10mBar all the way to 100bar or from 29.62"hg (a 99% complete vacuum) all the way to 1,450psi.

[greasybob]

that's cool, thanks for the charts and the explanation.