Sciencemadness Discussion Board

Do Walgreens Instant Cold Packs still contain Ammonium Nitrate?

Hurricoaster - 25-10-2016 at 10:14

Yesterday, I read this thread, and decided I would try to purify some ammonium nitrate. I bought some instant cold packs from Walgreens, and emptied the prills into an old water bottle. I then added 300ml of water to a beaker, and started adding the prills until they wouldn't dissolve anymore (it turns out what I thought was un-dissolved ammonium nitrate was actually a lot of anti-caking agent, but oh well). I then added another 200ml of water to dissolve the rest, then filtered the solution. The coffee filter caught all of the anti-caking agent, and I washed the beaker out, then put the filtered ammonium nitrate solution back in. I put this on a hot plate on medium-low heat, so that I could see water vapor coming off, but the solution did not come to a rolling boil (my hot plate doesn't let me choose an exact temperature, so I wanted to be sure I didn't boil off the ammonium nitrate). I left it this way overnight.

When I came back in the morning, all of the water was gone, and at the bottom of my beaker was a hard, white substance. I had to pound it with a butter knife to break it apart. I took a chunk of this, and tried to burn it. Instead of burning, though, it just melted! Is ammonium nitrate supposed to do that? I thought it was supposed to burn on its own, but maybe I'm wrong. How can I make sure what I have is really ammonium nitrate? Alternatively, can anyone else confirm that the Walgreens instant cold packs still contain ammonium nitrate?

Here is a picture of the resulting substance, if that helps:

XN0gqdy.jpg - 983kB

XN0gqdy.jpg - 983kB

MrHomeScientist - 25-10-2016 at 11:17

Last time I bought them several months ago they did. The other possibility is urea.

I don't think ammonium nitrate burns on its own usually. If you can, convert it to potassium nitrate and mix that with an equal volume of sugar to see if that burns. Or try adding a solution of a base to your suspected ammonium nitrate, and it should evolve ammonia gas. I'm not sure how urea would react though, so those tests might not be specific.

Maroboduus - 25-10-2016 at 11:37

Check the melting point. I'ts only around 160-170, you can do that with a MP tube and thermometer in a flask full of cooking oil.


gdflp - 25-10-2016 at 12:37

Quote: Originally posted by MrHomeScientist  
Last time I bought them several months ago they did. The other possibility is urea.

I don't think ammonium nitrate burns on its own usually. If you can, convert it to potassium nitrate and mix that with an equal volume of sugar to see if that burns. Or try adding a solution of a base to your suspected ammonium nitrate, and it should evolve ammonia gas. I'm not sure how urea would react though, so those tests might not be specific.

Urea will similarly release ammonia upon reaction with a base. The reaction of an alkali nitrate with sugar however, should be characteristic.

camerican - 25-10-2016 at 21:43

Somewhat off-topic, but CAN from Rival brand instant cold packs is an acceptable source of AN. The process of dissolving the AN and evaporating the solvent is much less tedious if alcohol is used instead of water.

AngelEyes - 26-10-2016 at 07:51

A different test is to simply dissolve an appreciable amount of what you suspect to be Ammonium Nitrate in water. It's an endothermic reaction and the beaker / glass / whatever will cool down as the nitrate dissolves, often quite markedly. Might be easier than melting in a flask of oil...

XeonTheMGPony - 26-10-2016 at 07:57

Quote: Originally posted by AngelEyes  
A different test is to simply dissolve an appreciable amount of what you suspect to be Ammonium Nitrate in water. It's an endothermic reaction and the beaker / glass / whatever will cool down as the nitrate dissolves, often quite markedly. Might be easier than melting in a flask of oil...



So does :
Ammonium sulfate
Urea
Cal Ammonium nitrate mixtures
and quite a few others that I can not recall the name off hand

Brom - 26-10-2016 at 08:00

You could add some hydrochloric acid and see if it reacts with copper to determine if it is a nitrate salt. If it tests positive for nitrate and also releases NH3 upon addition of NaOH it would have to be ammonium nitrate

Maroboduus - 26-10-2016 at 08:16

Quote: Originally posted by AngelEyes  
A different test is to simply dissolve an appreciable amount of what you suspect to be Ammonium Nitrate in water. It's an endothermic reaction and the beaker / glass / whatever will cool down as the nitrate dissolves, often quite markedly. Might be easier than melting in a flask of oil...


1: Put the MP tube tied to the thermometer in the oil.
2: heat the oil

Slightly less work than making french fries.

If you're a Tater Tots in the oven kind of guy then you should probably just buy your ammonium nitrate on amazon.
EDIT:

The solubility is unusual. more than 1:1 at 0C, and 10:1 at 100C.
You might be able to eliminate quite a few other possibilities by checking solubility.

[Edited on 26-10-2016 by Maroboduus]

OneEyedPyro - 26-10-2016 at 17:02

You could mix it with some sulfuric acid, you should get HNO3 fumes when you blow on it and if you add some copper wire it will produce NO2 upon heating.

AngelEyes. Obviously anything found in cold packs is going to produce an endothermic reaction when added to water.

Brom - 26-10-2016 at 17:55

I suggested using hydrochloric acid because it is the most readily available and cheap of the mineral acids and copper will not produce NO2 with anhydrous HNO3, some water is needed or the copper will form a passivation layer. So if concentrated sulfuric acid is used it must be diluted.

OneEyedPyro - 26-10-2016 at 23:13

I think the sulfuric acid stops the passivation effect of the HNO3. It worked for me with 98% sulfuric and dry ammonium nitrate.

[Edited on 27-10-2016 by OneEyedPyro]

AngelEyes - 27-10-2016 at 05:40

Quote: Originally posted by OneEyedPyro  

AngelEyes. Obviously anything found in cold packs is going to produce an endothermic reaction when added to water.


Yes, of course, not sure what the hell I was thinking...

Brom - 27-10-2016 at 10:25

That is interesting that the sulfuric acid would prevent passivation. I will have to do some experiments with this such as placing copper in anhydrous nitric acid then adding conc. Sulphuric acid and observe what happens.

Brom - 27-10-2016 at 10:50

I just mixed some ammonium nitrate with concentrated sulphuric acid and added a piece of copper wire and after 10 minutes at 60 degrees c. no reaction was observed. Upon addition of water NO2 was produced. And i know it is not a good idea to add water to concentrated acids but i was careful.



[Edited on 27-10-2016 by Brom]

OneEyedPyro - 27-10-2016 at 11:47

Interesting, when I do it I get a nearly instant reaction. It begins boil and copious amounts of NO2 is generated.
I'm using a wad of fine copper wires from lamp cord rather than one solid piece of copper, I suspect the greater surface area is what's allowing this to happen. I also wonder if my acid is truly 98%.

Brom - 27-10-2016 at 12:24

My acid is reagent grade from EMD. I used my pure stuff so i was sure i had no water involved. But i added quite a bit of water before NO2 began to bubble out so i wouldn't think our reagents would be different enough to give different results. Ill give it a try with some copper with a higher surface area.




MineMan - 27-10-2016 at 18:09

Just mix it with 50% mg powder and see if it lights, take out the suspense man!

Jimbo Jones - 28-10-2016 at 01:31

Magnesium powder is not always available. There is even simpler way. Make some concentrated solution of the suspected AN and soak a sheet of newspaper with it. Dry, roll and light the resulted “smoke bomb”. If the crystals are AN or a mixture with AN, the paper will burn with a lot of smoke.

Maroboduus - 28-10-2016 at 08:53

It seems this stuff is probably either Ammonium Nitrate or Urea.

If he just heats a pinch of it on a spoon, shouldn't it make N2O if AN, and NH3 if Urea?

That would be an obvious difference in odor.

And if it doesn't melt fairly quickly it would be some other salt.


NitratedKittens - 29-11-2016 at 02:45

Quote: Originally posted by Maroboduus  
It seems this stuff is probably either Ammonium Nitrate or Urea.

If he just heats a pinch of it on a spoon, shouldn't it make N2O if AN, and NH3 if Urea?

That would be an obvious difference in odor.

And if it doesn't melt fairly quickly it would be some other salt.


Bad news, i just did this test on what i thought was ammonium nitrate from a cold pack, it was urea :(

XeonTheMGPony - 29-11-2016 at 17:31

Wall mart cold packs seem to be cal ammonium Nitrate here in Canada still, just add some ammonia to precipitate out the cal, vacuum filter and dry.

CharlieA - 29-11-2016 at 19:11

Today I bought "up and up" cold packs from Target. A box of two cold packs cost about $3.50 USD and contained a total of about 250 g of ammonium nitrate (about $7 per pound). I have not yet determined the purity of the ammonium nitrate.

Laboratory of Liptakov - 5-12-2016 at 09:52

Here is video, difference between urea and AN on the copper plate , heated simply test. Maybe help it , for you and us. Dr.
https://www.youtube.com/watch?v=URu6Z79U3EA

npassbbi - 2-5-2017 at 19:23

I've been wondering the same thing about some cold packs I bought from walgreens here in the states. I did some tests tonight, and based on solubility (about 108g/L) and pH of the saturated solution (7, using hydrion paper), it looks like they're urea at this point.

JJay - 2-5-2017 at 19:30

Walmart has some cheap ammonium nitrate cold packs sold individually in the outdoor section.

yobbo II - 3-5-2017 at 00:19

Quote: Originally posted by XeonTheMGPony  
Wall mart cold packs seem to be cal ammonium Nitrate here in Canada still, just add some ammonia to precipitate out the cal, vacuum filter and dry.


How does that work. Is the 'cal ammonium Nitrate' a double salt or it it calcium carbonate (lime) + ammonium nitrate mixed.

Yob

JJay - 3-5-2017 at 03:36

Calcium carbonate is chalk; lime is calcium hydroxide.

I'm also curious about exactly what calcium ammonium nitrate is.

yobbo II - 3-5-2017 at 05:18

Quote: Originally posted by JJay  
Calcium carbonate is chalk; lime is calcium hydroxide.

I'm also curious about exactly what calcium ammonium nitrate is.


I did not know that 'lime' was calcium hydroxide. It tends to be used loosely by lay people for a lot of things that are calcium related.
Ground limestone, rocks composed of mainly calcium carbonate that are ground up, is refered to as 'lime' (for spreading on land) by the consumer and industry making it.
Calcium carbonate rocks (lime stone) when heated strongly, convert to CaO. The CaO is refered to as 'burned lime'.
When water is added to the CaO, the product, calcium hydroxide, is called hydrated lime. Heat is evolved in this process.
'Lime wash' or 'white wash' is calcium hydroxide and water.
This is in europe anyways, perhaps different in USA.

Calcium Ammonium Nitrate (CAN) used as fertilizer is usually a physical mixture of ammonium nitrate and ground limestone (crushed calcium carbonate rocks). Sometimes dolomite is used instead of the ground limestone (USA?).
There is an actual double salt that should be called ammonium calcium nitrate that is used for fertilizer (not very common if it exists at all in europe). It is obviously different from the physical mixture of Ca carbonate and AN.

ACN = H4CaN4O9

Will ammonium calcium nitrate, when dissolved in water, cause the temperature to drop? Can it be used in cold packs?

http://www.chemspider.com/Chemical-Structure.146035.html

There was a picture of ammonium calcium nitrate fertilizer on the board lately, what thread was it in?


[Edited on 3-5-2017 by yobbo II]

XeonTheMGPony - 3-5-2017 at 06:35

Quote: Originally posted by yobbo II  
Quote: Originally posted by XeonTheMGPony  
Wall mart cold packs seem to be cal ammonium Nitrate here in Canada still, just add some ammonia to precipitate out the cal, vacuum filter and dry.


How does that work. Is the 'cal ammonium Nitrate' a double salt or it it calcium carbonate (lime) + ammonium nitrate mixed.

Yob


It is a double salt, AN + CaN it is literally the floor sweepings of fertilizer plants, I have found dirt, bugs in it in the past!

Precipitate out the Ca by adding ammonia hydroxide to convert it to all NH4NO3 and CaOH.

and yes it gets nice and cold, warm day you get frost on the tube.
[Edited on 3-5-2017 by XeonTheMGPony]

[Edited on 3-5-2017 by XeonTheMGPony]

JJay - 3-5-2017 at 09:51

Quote: Originally posted by yobbo II  


I did not know that 'lime' was calcium hydroxide. It tends to be used loosely by lay people for a lot of things that are calcium related.

[Edited on 3-5-2017 by yobbo II]


It is true that you can buy "garden lime" consisting of calcium carbonate. They also sell dolomite as lime sometimes. But really, lime is supposed to be calcium hydroxide; you can avoid confusion by calling it hydrated lime. Slaked lime is calcium oxide. Calcium carbonate is chalk, but hardly anyone wants to spread chalk on their garden, so it is sometimes sold under the name lime for marketing reasons.

Melgar - 3-5-2017 at 10:37

So much bad info here.

First, the easiest way to tell which one you have is to melt a prill to decomposition on foil, then carefully smell the vapors. NH4NO3 usually has a slight NOx smell to it if you evaporate it quickly. There's also N2O released, which has no smell, but only if you're very careful with heating it will there be no smell at all. Urea decomposes to a white solid, releasing ammonia. The white solid is cyanuric acid and has a MUCH higher decomposition temperature, but it will all decompose eventually. Warning: cyanuric acid decomposition could potentially release cyanide, although cyanate is more likely. Ca/NH4 nitrate will leave behind a white ash that will not decompose even if you heat it to glowing. There's your 30-second test for cold packs. You're welcome, Mr. Pinkman.

Calcium/ammonium nitrate is just nitric acid neutralized with a mixture of calcium carbonate and ammonia; calcium carbonate being a much cheaper base. Lime can refer to many calcium compounds, usually calcium carbonate (lime or limestone), calcium hydroxide (hydrated lime), and calcium oxide (quicklime, slaked lime). Calcium oxide is made by calcining calcium carbonate with a release of CO2. Calcium hydrate is made by reacting calcium oxide with water, and incidentally, is a major component of cement and mortar. So is quicklime, I believe. Ca/NH4 nitrate isn't floor sweepings, it's just nitric acid neutralized with unprocessed limestone, with all the impurities included. They send the same shit to farms too; that's basically all the factory makes.

yobbo II - 3-5-2017 at 10:44


In more 'scientific circles' lime is calcium hydroxide.
Lime is a very old and very broadly used term.

From https://en.wikipedia.org/wiki/Agricultural_lime

Agricultural lime, also called aglime, agricultural limestone, garden lime or liming, is a soil additive made from pulverized limestone or chalk. The primary active component is calcium carbonate.

Million of tons of calcium carbonate (ground limestone or ground chalk) are spread on fields each year throughout the world.


"Slaked lime is calcium oxide."

Slaked lime is calcium hydroxide, the calcium oxide having been 'slaked' with water.
https://en.wikipedia.org/wiki/Calcium_hydroxide


Calcium oxide (burned lime (heated calcium carbonate)) is also called quick lime.
(my neck of the woods anyways)

https://en.wikipedia.org/wiki/Calcium_oxide

Most CAN around the world is composed of a physical mixture of ammonium nitrate + (shall we say) 'lime'. This lime is usually calcium carbonate (ground up limestone or chalk rock). Sometimes dolomite is used.

The double salt (ACN) is not so common (IMO). It may be available in your neck of the woods of course.

Can anyone post a picture or link to a fertilizer bag of ACN?

Perhaps quick lime should be renamed 'Heat-up-me-dinner-lime'.

https://en.wikipedia.org/wiki/Self-heating_can


yobbo II - 3-5-2017 at 11:26

Quote: Originally posted by Melgar  


, I believe. Ca/NH4 nitrate isn't floor sweepings, it's just nitric acid neutralized with unprocessed limestone, with all the impurities included. They send the same shit to farms too; that's basically all the factory makes.



Calcium/ammonium nitrate is just nitric acid neutralized with a mixture of calcium carbonate and ammonia; calcium carbonate being a much cheaper base. Lime can refer to many calcium compounds, ......................
............... I believe. Ca/NH4 nitrate isn't floor sweepings, it's just nitric acid neutralized with unprocessed limestone, with all the impurities included. They send the same shit to farms too; that's basically all the factory makes.



You forgot to mention the ammonia in the formula for 'the shit' fertilizer above. Is this correct. Its just calcium nitrate if there is no ammonia.


What is the formula of this {Calcium/ammonium nitrate} you speak of. (excluding any shit there may be there).
Is it this double salt or something else.
http://www.chemspider.com/Chemical-Structure.146035.html

To give the formula from the above page:
H4CaN4O9

Does this double salt appear in cold packs?
Will this double salt lower the temperature when you dissolve it in water (is it even suitable for cold packs from this point of view at all)?



Calcium Ammonium Nitrate (CAN) is a loosely used term.

What a ramble of a thread.

Yob

[Edited on 3-5-2017 by yobbo II]

yobbo II - 3-5-2017 at 11:40


https://en.wikipedia.org/wiki/Calcium_ammonium_nitrate

wiki has some good confusing info on Calcium Ammonium Nitrate. It is written is consusion style so that you do not know when they say calcium ammonium nitrate are they referring to calcium carbonate + ammonium nitrate (physical mixture) or the double salt ammonium calcium nitrate.

Attached is a description of 'calcium ammonium nitrate' CAN containing no calcium!!

EDIT:
The thread that shows the bag of Double salt, Ammonium Calcium Nitrate fertilizer (says it on the bag) is here:
http://www.sciencemadness.org/talk/viewthread.php?tid=73415
Picture reposted below.
This stuff is (imo) very rare in europe. Could be wrong.


http://www.sciencemadness.org/talk/files.php?pid=480681&...

A thesies on ammonium nitrate based fertilizers is attached. You'll be 'black in the face' reading it.
It's all rather complicated with lots of small amounts of different additives that can be used for various purposes.



Attachment: YaraBela_CAN_27_(S)_20170503.pdf (481kB)
This file has been downloaded 461 times


[Edited on 3-5-2017 by yobbo II]

Attachment: properti.pdf (6.9MB)
This file has been downloaded 905 times


CharlieA - 3-5-2017 at 17:05

In Nov. I bought 2 instant cold packs from Target for about $3.50 with tax. They totaled about 210g of pale yellow spheres. I haven't done anything with them yet.

symboom - 21-7-2017 at 23:05

Oops
The previous page post quote
Wall mart cold packs seem to be cal ammonium Nitrate here in Canada still, just add some ammonia to precipitate out the cal, vacuum filter and dry.

If any one has cold packs from walmart the brand that they sell is ace brand by 3m which contains calcium ammonium nitrate just so you know


Thats what it seems like to me
Cheap urea: doller store
Semi cheap calcium ammonium nitrate :walmart
Expensive ammonium nitrate :walgreens

Test for nitrate melt it on a piece of copper
If it is nitrate it will turn blue urea does not

[Edited on 22-7-2017 by symboom]