boobmaan
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Saturated CaCl2 Ice Bath
Can a saturated solution of CaCl2, combined with cocktail ice, reach and maintain sub-0c temperatures?
Just curious... ;-)
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tastyphenome
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www.google.com
"lowest temp ice bath cacl2"
first link: http://en.wikipedia.org/wiki/Cooling_bath
first info paragraph:
A bath of ice and water will maintain a temperature 0°C since the freezing point of water is 0°C. However, adding a salt such as sodium chloride
will lower the temperature through the property of freezing-point depression. Although the exact temperature can be hard to control, the ratio of salt
to ice influences the temperature:
-10°C can be achieved with a 1 to 2.5 ratio of calcium chloride hexahydrate to ice.
-20°C can be achieved with a 1 to 3 ratio of sodium chloride to ice.
-40°C can be achieved with a 1 to 0.8 ratio of calcium chloride hexahydrate to ice.
thankyou
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boobmaan
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Yes. Google. Thanks.
The question was asking if a saturated solution of CaCl2 and block/cocktail ice can reach and maintain a sub-zero temp. I'm not talking about crushed
ice or shaved ice. I'm talking about the ice you get at the supermarket or convenience store. Also, this is OTC CaCl2, not CaCl2·6H2O... I'm
talking damprid.
In this thread:
http://www.sciencemadness.org/talk/viewthread.php?tid=10444#pid125424
chemrox says:
| Quote: |
My CaCl2 solution is in the freezer at -14*C which is about where I want it for the use I have in mind. I used really cheap dessicant from an RV
supplier. |
I have not asked chemrox on his procedure... Does anyone have any more advice/experience using CaCl2 & ice to achieve subzero temps? Would I
just crush the ice and add the CaCl2? It seems to me that a solution would be easier, but I have no experience. I'm just trying to gather as much
information as possible before expending resources! And I would rather not mess with acetone or Isopropyl to get the temp down...
Quote: Originally posted by tastyphenome  | www.google.com
"lowest temp ice bath cacl2"
first link: http://en.wikipedia.org/wiki/Cooling_bath
first info paragraph:
A bath of ice and water will maintain a temperature 0°C since the freezing point of water is 0°C. However, adding a salt such as sodium chloride
will lower the temperature through the property of freezing-point depression. Although the exact temperature can be hard to control, the ratio of salt
to ice influences the temperature:
-10°C can be achieved with a 1 to 2.5 ratio of calcium chloride hexahydrate to ice.
-20°C can be achieved with a 1 to 3 ratio of sodium chloride to ice.
-40°C can be achieved with a 1 to 0.8 ratio of calcium chloride hexahydrate to ice.
thankyou |
[Edited on 10-3-2012 by boobmaan]
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Bot0nist
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You can get sub zero temps with most salt/ice baths easily.
The damp rid will hydrate when exposed to moisture...
Get a thermometer and dip it in the mix.
[Edited on 10-3-2012 by Bot0nist]
U.T.F.S.E. and learn the joys of autodidacticism!
Don't judge each day only by the harvest you reap, but also by the seeds you sow.
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peach
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According to this table of frigorific mixtures, dry ice like temperatures can be achieved with regular ice and dilute sulphuric.
I have actually attempted that, thrice, but struggled to get it below regular ice / salt temperatures. It'd be interesting for others to try and see
if they can get it down that low. Perhaps the sulphuric I was using wasn't dilute enough, and the heat of further dilution was overriding the heat
absorbed by the melting point depression.
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boobmaan
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CaCl2 AND NaCl?
What about a combination of NaCl and CaCl2? A saturated solution?
If so, procedure? Thank you!
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Bot0nist
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Procedure? Come on man, just make a saturated solution of the salts in water (till no more dissolves), add crushed ice and mix. Keep in the freezer
for a bit to help. Then stick in the thermometer to see what you have. Experiment with ratios till you get what you need. Simpler than making ice
tea...
U.T.F.S.E. and learn the joys of autodidacticism!
Don't judge each day only by the harvest you reap, but also by the seeds you sow.
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peach
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Buy a bag of ice cubes. Wrap some in an old tea towel and place on concrete floor. Smash to bits with the bottom of a pan. Put a tupperware box on the
kitchen scales, weigh in some ice, pour over the corresponding amount of table salt, give it a good stir with a spoon, done.
If you have snow where you live, that's better. And you can guesstimate the salt ratio by eye once you've seen roughly how much it is.
I seem to remember 400ml of said mixture keeping the temperature in a dewar at -20 for about 45 minutes to an hour before it started going back up
much. I'd had the dewar in the freezer prior to that I think.
If you don't have any snow, and don't like smashing things with pans, Mr. Evil Face Frosty is here to help.
[Edited on 11-3-2012 by peach]
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boobmaan
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lol. I had one of those too!(never noticed the Evil Face though ;-).
Thank you everyone!
| Quote: Originally posted by peach | If you don't have any snow, and don't like smashing things with pans, Mr. Evil Face Frosty is here to help.
[Edited on 11-3-2012 by peach] |
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ScienceSquirrel
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Thread Pruned
13-3-2012 at 05:18 |
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