How to Make Potassium Nitrate





Introduction: How to Make Potassium Nitrate

Make Potassium Nitrate from Instant Cold Packs and Potassium Hydroxide

Warning: This reaction will produce large quantities of toxic ammonia gas. Perform the reaction outside or in a fume hood. Potassium hydroxide is highly corrosive; wear gloves when working with it.

Some instant cold packs contain ammonium nitrate as their active ingredient and when mixed with potassium hydroxide will produce potassium nitrate and ammonia gas.

Get an instant cold pack that clearly says it contains ammonium nitrate, cut it open, and pour the contents into a container. If its unused there will be a water pouch that you can discard. The rest of the pack is ammonium nitrate. Usually its coated in an anti-caking agent so it'll be off-color.

If you're using an already used instant cold pack then filter out the liquid and let it evaporate until it's dry. The crystals will be ammonium nitrate.

Take 80 grams of ammonium nitrate and dissolve in 70 milliliters of hot water. This will take some time so be patient. It will take even longer in cold water so use hot water when you can.

If it has an insoluble anti-caking agent then you need to filter it off through a coffee filter.

Separately, measure out 56 grams of potassium hydroxide. Potassium hydroxide is sold online to make homemade soaps and for biodiesel.

Add just enough water to completely dissolve the potassium hydroxide.

When both solutions are clear and ready, add the ammonium nitrate solution to the potassium hydroxide solution. This step will produce large amounts of ammonia gas and must be done outside or in a fumehood.

Leave the solution in a very well-ventilated area (outside is best) for all the water and ammonia to evaporate. You can also boil the solution to dryness, just remember it is still producing ammonia.

Now you have potassium nitrate!

To test it, mix a small portion with an equal amount of sugar and set it on fire. Normally pure sugar does not burn but if the potassium nitrate works then it will flare up in a purplish pink flame.

You can also make sodium nitrate by substituting the potassium hydroxide for 40grams of sodium hydroxide and follow the same procedure as the video.

In an upcoming video we will show how to make sodium nitrate from ice packs and baking soda. This requires a slightly different procedure than this video.

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    will lye work in place of Potassium hydroxide?

    So called "37-0-0" fertilizer is mostly Ammonium Nitrate.
    (In the spring say to the farm store clerk "I'm making a "Straw Bale Garden"." No further questions.)
    Potassium Chloride is found in some "Ice Melting Compounds" if you are in Canada or the Northren United States.
    Just disolve the Ammonium Nitrate in boiling water, one gallon can disolve as much as sixty-four pounds of Ammonium Nitrate, filter off the insolubles, then outside, slowly stir in the Walmart Potassium Hydroxide drain cleaner.
    The addition of the Potassium Hydroxide will cause the solution to heat up, maybe even boil, and give off copious ammounts of amonia gas, (DO NOT BREATH THE FUMES- POISON), so do it out behind the barn.
    As you stir, Potassium Nitrate crystals will form and sink to the bottom. The Potassium Nitrate can later be removed by filtering out the crystals and then washing out the water with denatured alcohol.
    Alow the alcohol to evaporate and store the crystals in an air tight container.

    kindly guide me that, how i can make potassium nitrate crystals form sodium nitrate and potassium chloride??

    extract from poo intense earth, like around barns, and if you live in cities there are place people pee all the time (in a lot behind a bush) or horse academies. I believe you can put the dirt back when you are done. Since you rinse the soil for nitrates then process further.

    look it up

    As a person with miltiple scars anddamaged eyes, (i was 11) I will tell you unless you are in a controlled lab you are foolish to do most chemistry shown here. And any time I can , I go to fireworks shows they are awesome. Enjoyable are the REDOX reactions that are exothermic. (did I get that right).


    ammonium nitrate is less reactive than potassium nitrate, making it less better for pyrotechnics, also it is hydroscopic: it attracts water. That means it cakes together and gets annoying. anyway, potassium is better to use.

    KNO3 is very hygroscopic

    Not nearly as hygroscopic as sodium nitrate or ammonium nitrate. In fact, for most environments, KNO3 is not hygroscopic. The relative humidity must be very high before it starts absorbing water.

    Thats weird, because my KNO3 if left outside turns into a puddle after 2 days, I live in Western Australia, the current humidity is 72% It may not be comparitively hygroscopic, but it still does trap enough water to become visually wet

    Why would you put it outside? I never put any of my chemicals outside.

    It was to demonstrate the hygroscopic nature of KNO3, all nitrates are soluble and most are hygroscopic and that was the first and only time I have ever left a chemical in the open