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Safe Video Demonstration Sodium and Potassium Exploding In Water

video Safe Video Demonstration Sodium and Potassium Exploding In Water

The demonstrations of many remarkable experiments include a high safety risk (e.g. the reaction of large pieces of sodium/potassium with water; the reaction of potassium with liquid bromine; the reaction of sodium with concentrated sulfuric acid, etc.). Chemistry teachers and instructors are usually reluctant to perform experiments that include a hazard. As a result, a number of fascinating experiments remain unknown to the public.

A very violent reaction of sodium and then potassium with water.
2Na + 2H2O --> 2NaOH + H2

2K + 2H2O -->2KOH + H2

Small pieces of these metals are dropped in water.

27 comments

Sep 28, 2009. 8:30 AMgeodez says:

elephant noises.

Sep 1, 2009. 4:51 PMantienoob says:

is this video also on youtube because my computer is playing up and i cant view it.

Jul 9, 2008. 4:06 PMcodongolev says:

did anyone notice that the potassium made the water green, but then it exploded and turned purple?

Jun 20, 2009. 6:11 PMlobo_pal says:

That was a Ph indicator. It turned purple because of the presence of NaOH in the water after the reaction.

Mar 29, 2009. 6:48 PMResident Expolsives Expert says:

(removed by author or community request)

Apr 2, 2009. 3:18 PMcodongolev says:

just shake to combine the potassium with the water, draw while you still can, then run and hope it doesn't blow up! if it doesn't, then keep drawing in purple. if it does, then hey! abstract art.

Jun 11, 2009. 1:15 PMmr.space says:

that probably universal indicator solution, green is neutral, the purple indicates a strong alkali solution i.e. potassium hydroxide

Nov 26, 2008. 2:23 PMhigh1 says:

yeah, I did, it is strange...

Jun 17, 2009. 2:00 AMadsa says:

As an alternative fill a beaker with water to create a positive meniscus. Add 2-3 drops of phenolphthalein to the water and then place a piece of filter paper on the beaker ensuring the paper absorbs some of the water. Place some Na onto the paper, stand back and enjoy. Unfortunately my school is not allowed to have K or Na anymore, so keep your videos coming!!!

Apr 11, 2009. 11:27 AMTHESTU says:

super cool.

Apr 18, 2008. 10:12 AMfd93 says:

we also did that but we used some other alkilane that i cant remember. i think ribidium or cesium it was realy ausome.

Feb 12, 2009. 5:56 PMTubetech762 says:

Try lithium if you can get any. It isn't radioactive like cesium and the reaction is quite entertaining. Lithium is VERY reactive and when contact with water the reaction is explosive so be VERY carefull

Feb 12, 2009. 9:24 PMfd93 says:

if you have lithium my fave is to use it in fireworks makes great deep reds

Feb 13, 2009. 3:19 PMTubetech762 says:

I was reffering to metallic lithium but in this form it is hard to find, as few people are experianced enough to handle it safely. But you are correct lithium makes a beautiful red

Feb 10, 2009. 3:38 AMHolden_vy_s says:

I HIGHLY doubt you used Rubidium. And i doubt you used Caesium either, they were most likely Sodium or Potassium.

Feb 10, 2009. 9:50 AMfd93 says:

ya i have since checked with my teacher it was like 5 grams of potassium

May 11, 2008. 11:49 AMheavy.metal.nguyen says:

I doubt you used rubidium in a school science experiment. Alkali metals react very violently when it reacts with water.

Mar 15, 2008. 5:02 PMFunkNattidelic says:

I noticed that the thing that the crap was put in was green before the explosion and purple after the explosion. any body else notice that??

Mar 20, 2008. 9:15 PMScar21 says:

Yeah, you can even see the color change when it goes to slow motion. And the thing the crap was put into was water. And the crap is Potassium. We did this at our school, but with sodium instead. It caught fire, but not actually exploding like that :D

Mar 20, 2008. 9:44 PMconrad2468 says:

go to unitednuclear.com to get some sodium and other reactive elements plus other junk that you might want

Apr 1, 2008. 3:46 AMScar21 says:

That's right. We did that too. I remember now.

Mar 29, 2008. 8:41 PMmetroidfreak108 says:

I think they added a Ph tester to the water since water is normally green with it. After potassium hydroxide is produced, it turns purple or pink cause I think potassium hydroxide or whatever is made is somewhat acidic...?