[arian675]

Hey guys,

New member here. I'm looking for two safe liquid components that freeze almost instantly when they come in contact with each other. imagine a tube that contain one element and is connected to a separate coin size bubble that contains the second element. I'd like to be able to freeze the first element by releasing the second one from the bubble to the tube.

do such chemicals exist? is this experiment possible?

[Arkcon]

Briefly, no, this isn't possible, as stated.  Things don't freeze instantly, or boil by mixing, generally.  Freezing and boiling, of water for example, requires a great deal of energy -- more then you can get by a simple chemical reaction.  Yes, some very volatile substances boil with the heat of the human hand, and of course, molten metals freeze into solid metal as they cool.  But it doesn't seem like you're talking about situations like that, as you describe "safe" liquids in tubes, and the like.

[Borek]

Does it have to be freezing, or any solidification will do?

[billnotgatez]

@arian675
I am thinking you want 2 compounds that are liquid to combine into a solid rather than freezing?
And, you want this to be a safe process.

as Borek suggested

[arian675]

well, it doesn't necessarily have to "freeze" but it has to become very chilled.

For some reason i have a vague memory of this little patch i had as a kid with some gooey material in it with two buttons...one would instantly heat the patch up that we used to warm up in winter and the other would cool it to the point that it would get uncomfortably cold after awhile.

and when i say buttons, i don't mean any electrical circuit. the button would sorta break in like cracking a glow  stick.

[billnotgatez]

http://en.wikipedia.org/wiki/Instant_cold_pack
Instant cold pack

An instant cold pack is a device that consists of two bags, one containing water, which holds a second bag containing ammonium nitrate. When the inner bag of ammonium nitrate is broken by squeezing the package, it is allowed to dissolve in the water in an endothermic reaction. This reaction absorbs heat from the surroundings, quickly lowering the pack's temperature.[1]

Instant cold packs are a convenient direct replacement for crushed ice used as first aid on sport injuries. It is also important not to refrigerate before activation. This may result in frostbite if used for prolonged periods of time.

For safety reasons, instant cold packs have recently been developed without ammonium nitrate.[2]

Would the above link describe the kind of thing you are interested in doing

What I am not sure of is if you want solid or cold or both

[Arkcon]

Yes, I thought you were talking about the "pocket handwarmers" and "instant chill packs".  Those are little sealed chemical reactions that generate heat, or absorb some, when conducted in a small package.  However, its hard to get much energy out of, or absorbed by (that's how scientist define cold, as absorbing heat) a simple chemical reaction.  If you want lots of heat, you burn something.  If you need lots of cold, you melt lots of ice.  But for small amounts:
http://en.wikipedia.org/wiki/Instant_cold_pack
http://en.wikipedia.org/wiki/Heating_pad#Chemical

[arian675]

exactly..."instant chill packs". it's a relief to remember what it was called.

a few follow up questions:

a)description says it uses an "endothermic" process to collect heat from the surroundings, so what happens to the collected heat? would it be released back after a period of time?

b)is ammonium nitrate or this reaction as a whole dangerous if it comes in contact with skin?

c)and finally, im not a chemist nor do i have any chemical knowledge so i prefer not to do the experiment myself for safety reasons. are there public labs that i can pitch in my idea and have it done by professionals?