What's the name of the thing that gets heated when reacted with water?

The Pentium Guy

Diamond Member
Jan 15, 2005
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....I'm helping a friend with his project for deicing a windshield and there's something in my head that I just can't pinpoint. I know what it does, but I can't remember the name.

In wars, where food is scarce, soldiers have these packs of food that they pour water into. The food is covered in a plastic wrapping, but around the plastic there's this .... something. This thing reacts with water, and instantaneously heats up (heating up the food).

I can't remember what that 'something' is. For some reason I'm thinking of "self-heating metals".

Anyone want to jog my memory?

Thanks,
-The Pentium Guy
 

The Pentium Guy

Diamond Member
Jan 15, 2005
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Google is god.

http://www.palmbeachpost.com/storm/cont.../getready/before/selfheating_food.html
It took a California company named OnTech seven years and $24 million to create the self-heating cans, which are activated by pushing a plastic button on the bottom. Water flows into a sealed inner cone filled with quicklime, which is mostly calcium oxide. A chemical reaction heats the coffee to a pleasant 145 degrees in six to eight minutes, the amount of time it might take to order, pay for and receive a latte from a barista.
 

jfall

Diamond Member
Oct 31, 2000
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Those meals are called MRE's (meals ready to eat) and are actually pretty damn good btw :)
 

loup garou

Lifer
Feb 17, 2000
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Originally posted by: jfall
Those meals are called MRE's (meals ready to eat) and are actually pretty damn good btw :)
Yep, I had a couple in New Orleans. The self heating ones are cool!
 

neit

Senior member
Dec 6, 2001
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One of my chemical engineering professors (old fart, i think he retired this year) told us how you could buy it from the store a long time ago. He would put a small chunk of it in a coffee can, spit on it, and then seal it somehow (hehe, forgot the exact story), and it go BOOM!

Too bad everything interesting today is a 'hazardous material' and you can't get any if you wanted =(
 

Vette73

Lifer
Jul 5, 2000
21,503
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Originally posted by: shahbazq
One of my chemical engineering professors (old fart, i think he retired this year) told us how you could buy it from the store a long time ago. He would put a small chunk of it in a coffee can, spit on it, and then seal it somehow (hehe, forgot the exact story), and it go BOOM!

Too bad everything interesting today is a 'hazardous material' and you can't get any if you wanted =(


There are plenty of household items that can go boom. heck me and friends while in high school chem would take Chlorine and brake fluid. Put in a 2 liter and close the lid and run like heck. seconds later... BOOM. :)

 

skyking

Lifer
Nov 21, 2001
22,764
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Originally posted by: Marlin1975
Originally posted by: shahbazq
One of my chemical engineering professors (old fart, i think he retired this year) told us how you could buy it from the store a long time ago. He would put a small chunk of it in a coffee can, spit on it, and then seal it somehow (hehe, forgot the exact story), and it go BOOM!

Too bad everything interesting today is a 'hazardous material' and you can't get any if you wanted =(


There are plenty of household items that can go boom. heck me and friends while in high school chem would take Chlorine and brake fluid. Put in a 2 liter and close the lid and run like heck. seconds later... BOOM. :)

Hadn't heard of THAT one........<furiously scribbles notes> :evil:

 

Vette73

Lifer
Jul 5, 2000
21,503
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Originally posted by: skyking
Originally posted by: Marlin1975
Originally posted by: shahbazq
One of my chemical engineering professors (old fart, i think he retired this year) told us how you could buy it from the store a long time ago. He would put a small chunk of it in a coffee can, spit on it, and then seal it somehow (hehe, forgot the exact story), and it go BOOM!

Too bad everything interesting today is a 'hazardous material' and you can't get any if you wanted =(


There are plenty of household items that can go boom. heck me and friends while in high school chem would take Chlorine and brake fluid. Put in a 2 liter and close the lid and run like heck. seconds later... BOOM. :)

Hadn't heard of THAT one........<furiously scribbles notes> :evil:


Yep Chlorine (i.e dry pool cleaner you get at K-mart, target, etc...) has oxygen in it. The brake fluid releases the oxygen but also produces heat. Oxygen and heat = BIG flame. Oxygen and heat in a sealed container = BIG BOOM
Dry chlorine first then a little brake fluid then seal and run. Make sure the conatiner is 100% dry or it speeds it up. i.e. you don;t have enough time to seal said container.

If you do this play it safe, and a little goes a long way.

 

Howard

Lifer
Oct 14, 1999
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All alkali metals give off heat when reacted with water. I don't suggest you use them, though.
 

Analog

Lifer
Jan 7, 2002
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Originally posted by: Howard
All alkali metals give off heat when reacted with water. I don't suggest you use them, though.

yup. Just get some old high pressure sodium lamps, break open and put the filaments in water for some fun.