Last week i was interested in how a INSTANT cold pack works. So I opened the pack up and the ammonia nitrate was wet but not cold. Maybe the gel water pack leaked some time ago and the ammonia nitrate got cold but it only stayed cold for a certain amount of time(about a month)? And then when i opened it up it was dead like a battery with no power? So if I were to dry out the ammonia nitrate and put it in a zip lock bag and then pour water in it would it get cold? Or has it lost it's power like a battery?

 

I think it is ammonia nitrate because i remember hearing somewhere that it gets cold with water.

im not sure to be honest, although someone else will probably know.

 

any reason in particular why you dont just try it yourself seeing as you have the equipment with you?

it would get cold again. the reaction for dissolving ammonium nitrate is endothermic. when it comes out of solution the reaction is exothermic and it gains energy for it to lose again when it is put back into solution

it would get cold again. the reaction for dissolving ammonium nitrate is endothermic. when it comes out of solution the reaction is exothermic and it gains energy for it to lose again when it is put back into solution

 

 

dont u mean it loses energy to then be gained?

yeah, thats exactly what i mean. that's also the second time in the last few hours in which i have made that sort of mistake. i think the permanganate is going to my head

he`s perfectly correct, it`s re-usable for a near infinate amount of times, and the dryer you get the stuff the better the reaction

 

it`s nothing LIKE a battery, the energy used to drive the water off, is taken from the waters heat energy when re-added and so will get cold again and again and again ....

this stuff sounds great, ive read aboout it before but never bothered, how cold does it get? just a ruff idea.