The Naked Scientists
Toggle navigation
Login
Register
Podcasts
The Naked Scientists
eLife
Naked Genetics
Naked Astronomy
In short
Naked Neuroscience
Ask! The Naked Scientists
Question of the Week
Archive
Video
SUBSCRIBE to our Podcasts
Articles
Science News
Features
Interviews
Answers to Science Questions
Get Naked
Donate
Do an Experiment
Science Forum
Ask a Question
About
Meet the team
Our Sponsors
Site Map
Contact us
User menu
Login
Register
Search
Home
Help
Search
Tags
Member Map
Recent Topics
Login
Register
Naked Science Forum
On the Lighter Side
Science Experiments
compact NON-Toxic Endothermic reaction able to cool 20ouncs of fluid
« previous
next »
Print
Pages: [
1
]
Go Down
compact NON-Toxic Endothermic reaction able to cool 20ouncs of fluid
2 Replies
8872 Views
0 Tags
0 Members and 1 Guest are viewing this topic.
cmorr
(OP)
First timers
1
Activity:
0%
compact NON-Toxic Endothermic reaction able to cool 20ouncs of fluid
«
on:
05/11/2012 06:52:07 »
Hello,
I'm looking for a super compact non-toxic endothermic reaction that results in cooling 20 ounces of fluid where the heat is transfered through radiation and not convection. Thus not altering the 20ounces of liquid chemically, but still resulting with a 20-30 degree(F) drop in temperature. The reason for non-toxic is if the chemicals do mix it must still be safe to drink.
Logged
CliffordK
Naked Science Forum King!
6596
Activity:
0%
Thanked: 61 times
Site Moderator
Re: compact NON-Toxic Endothermic reaction able to cool 20ouncs of fluid
«
Reply #1 on:
06/11/2012 00:16:50 »
A place to start looking might be the
"instant cold packs".
According to the notes, they have traditionally included a mix of
ammonium nitrate
and water. The notes seem to indicate that it is only moderately toxic at pretty high doses, with the LD
50
about 2 grams per kilo (for the salt).
I don't think I'd want to drink a lot of it though.
There is also an ammonia nitrate free
InstaKoolâ„¢ Instant Cold Pack
consisting primarily of Urea: (NH
2
CONH
2
) & Biuret: (NH
2
CONHCONH
2
), PLUS Water. The published LD50 for rats and mice is around 11 to 15 g/kilo (of the solids). That is a LOT!!!
I presume it just gets pissed out in the urine.
The MSDS does list some GI symptoms, but they tend to be quite conservative. Still, I'm not sure about eating it.
Logged
CliffordK
Naked Science Forum King!
6596
Activity:
0%
Thanked: 61 times
Site Moderator
Re: compact NON-Toxic Endothermic reaction able to cool 20ouncs of fluid
«
Reply #2 on:
06/11/2012 10:56:48 »
Urea is apparently more digestible than biuret. However, both are apparently used as a cattle feed supplement, although it is also apparently more toxic to cattle than other animals.
Assuming the kidney function is fine, perhaps pure Urea + water might not be too bad.
Ok, I'm seeing notes:
600 ml water + 400g Urea will drop the temperature from about 20⁰C to about 3⁰C.
However, that would be A LOT OF UREA to eat. Even if you dropped it down to 60ml water + 40 g Urea, it would still be quite a bit, but perhaps more palatable (occasionally).
Logged
Print
Pages: [
1
]
Go Up
« previous
next »
Tags:
There was an error while thanking
Thanking...