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Amaze A Science Class with Elephant Toothpaste

video Amaze A Science Class with Elephant Toothpaste
This experiment shows the decomposition of hydrogen peroxide catalyzed by potassium iodide. The reaction is done in a tall graduated cylinder so that the foamy product shoots out very quickly in a tall cylindrical shape; hence, the name elephant toothpaste.

Materials:
tall graduated cylinder (at least 500 ml)
food coloring
Dawn detergent
30% hydrogen peroxide (H202)
saturated solution of potassium iodide (KI)
disposable gloves
splint (optional)

Hazards:

1. Wear safety goggles. Also, wear disposable gloves when pouring 30% hydrogen peroxide, as it is a very strong oxidant.
2. Do not stand over the graduated cylinder because steam and oxygen are produced quickly.

Procedure:

1. Place a garbage bag or other covering on the lab table and possibly on the floor.

2. Fill the vial containing potassium iodide with water. Cap and shake until all the potassium iodide is dissolved (This should now be a saturated solution of KI made with 15 grams of KI and water.) Set aside.

3. Put on disposable gloves. Pour 80 ml of 30% hydrogen peroxide into a graduated cylinder.

4. Add about 40 ml of Dawn detergent to the hydrogen peroxide. Swirl to mix

5. Tilt the graduated cylinder and drip red and/or blue food coloring down the sides of the graduated cylinder to make your toothpaste striped

6. Quickly add the saturated solution of KI solution and stand back Be sure to move your hand away from the top of the graduated cylinder quickly or the hot foam will get on your hand and arm.

7. You may place a glowing splint in the foam to test for oxygen, but do not drop the splint into the graduated cylinder. The splint will relight indicating the presence of oxygen.

Discussion:

The rapid catalyzed decomposition of hydrogen peroxide produces O2 gas which forms a foam with the liquid detergent:

2H2O2 (aq) -> 2H2O + O2 (g)
The I-1ion is a catalyst for the reaction. The brown color of the foam is evidence of iodine in the reaction. It will stain clothes, skin, and carpet

Disposal:

Leave the gloves on while cleaning up. The foam and solution left in the graduated cylinder may be rinsed down the drain with excess water.

referance-http://library.thinkquest.org/10429/low/cool/labs/elephantlab.htm
54 comments
1-40 of 54next »
Jul 18, 2010. 3:50 PMyellowbrain says:
A few words on this experiment and Hydrogen Peroxide. Firstly if you are wishing to try this experiment I highly recommend you use Magnesium Dioxide as the catalyst instead of Potassium Iodide, It doesn't stain everything it touches like Iodides do. (also most metals work well as catalysts, Iron, Silver, copper all are really good, try iron filings :D) Secondly, Hydrogen peroxide above 6% is quite hard to obtain if you are not buying it from a chemical supplier, as a researcher, or business. 100% hydrogen peroxide essentially doesn't exist, at that concentrations near to 100% it decomposes explosively, and as such is near impossible to obtain anything higher than 70%. If you attempt to concentrate Hydrogen peroxide from a 3% or 6% solution, by evaporating the water (H2O2 boiling point is 15oC) you will in fact reduce the concentration as at higher temperatures the peroxide will decompose exponentially higher. Also be aware that peroxide is acid stabilized (a small amount of acid is added to prevent decomposition) and at pH of about 10 it will decompose on it's own in a matter of days. Good suppliers of lab grade (30-35%) peroxide are VWR and Sigma Aldrich, though these companies will definitely not sell to kids (under 18's) or to persons without legitimate reasons (for example I work in research of peroxide sterilization). Hydrogen peroxide, particularly of this grade is controlled as it is a precursor to a number of explosives. Hope this helps answer the questions which seem to appear in the comments If you wish to know more about Hydrogen peroxide, the following text is fairly comprehensive: "Hydrogen Peroxide" Schumb, Wentworth, Satterfield. 1955 ASC Monograph 128. (can be a bit hard to find however)
Sep 13, 2010. 5:45 AMpastorjoe777 says:
You can actually get 20, 30 even 40% H2O2 easily from a beauty supply shop. My 14 year old went in and bought it without any questions! >:-(

http://www.sallybeauty.com/40-Volume-Developer/SLNCAR67,default,pd.html
http://www.sallybeauty.com/Clear-Developer/SLNCAR61,default,pd.html
Oct 18, 2010. 10:47 AMyellowbrain says:
The links provided are for 20 and 40 vol peroxide.
The vol system is not the same as the % concentration.
the vol is the volume of oxygen generated when the volume of peroxide is decomposed.
So for a 1 liter solution of 40 vol (12%) peroxide this produces 40 liters of oxygen when decomposed.
As a guide each 1% is about 3.3 vol.

This is however a higher concentration then I expected to be available.
thankyou for your reply.
Sep 26, 2010. 11:38 PMScreamo says:
Front picture looks weirrdd
Oct 12, 2009. 5:41 AMjumpertoad says:
this is so totally awesome
Aug 15, 2009. 1:54 AMnfarrow says:
Looks like something from, "Demolition Man" with the car seen. LOL
Jul 10, 2009. 2:04 PMandi6 says:
Can't wait to try this!
Feb 13, 2008. 3:39 PMiamthemargerineman says:
WOAH! THIS IS SOOOO COOL!!!!!!!!!!!!!! mmm. I'm with the gorilla kid, where can we buy this stuff? Online...?
Jun 13, 2009. 12:26 AMminerug says:
you can get weak peroxide from most pharmacies, it is sold as antiseptic
Sep 19, 2008. 6:49 PMwotot2 says:
i think think you might be able to get the stuff at united nuclear.com, and they have a bunch of other cool stuff too.
Jun 29, 2008. 11:28 AMszechuan53 says:
think hindenburg. no shipments for you!
Jun 29, 2008. 5:00 PMiamthemargerineman says:
well then. i suppose not. i had some szechuan chicken the other day. it was yummy in my tummy.
Jun 29, 2008. 5:49 PMszechuan53 says:
you are a fish. i am the sun. I EAT YOU!!!
Jun 30, 2008. 11:45 AMiamthemargerineman says:
hmm... i never knew the sun had a digestive system. learn somethin new everyday dontchaaa?
Jun 30, 2008. 4:37 PMszechuan53 says:
well, i was actually going to roast you for my wife, Uranus
Jul 4, 2008. 5:19 PMiamthemargerineman says:
you are a funny one.
Jul 6, 2008. 4:40 PMszechuan53 says:
thank you, snakehead
Jul 23, 2008. 9:44 PMiamthemargerineman says:
actually. i'm a male jawfish. take THAT!
Jul 26, 2008. 8:36 AMszechuan53 says:
you smell like old people and snake poo, so i assumed you were a snakehead. it's only logical.
Aug 8, 2008. 5:25 PMiamthemargerineman says:
ouchie.
Aug 18, 2008. 3:24 PMszechuan53 says:
sorry smelly.
May 17, 2008. 1:45 PMmr.dr.prof.joel says:
no not online shipments of h2o2 over 7% are highly dangerous. when it is mixed with organic substances at significant concentrations, hazardous impact-sensitive compounds may result. Small amounts of other materials that contain catalysts (silver, lead, copper, chromium, mercury, and iron oxide rust) can cause rapid decomposition and an explosive pressure rupture of the containing vessel if it is not properly vented.
May 14, 2009. 12:08 PMspotty mcgee says:
check out what hydrogen peroxide does to your skin:

http://www.rocketbelts.americanrocketman.com/HP/HYDRO_PEROXIDE_BURNS.jpg

Oct 3, 2008. 10:01 PMTanners says:
it would be cool if you mixed helium somewhere in there and then it could make the bubbles float!
Sep 16, 2008. 9:10 PMIX Smith XI says:
Ooooooooooo dang that is f**king cool. Five stars
Jan 25, 2008. 6:33 PMGorillazMiko says:
Cool, but where can I get some of the chemicals? I don't think a store would sell them to a 13 year old kill, would they?
Jul 30, 2008. 3:12 PMszechuan53 says:
if you still have trouble, go here or here.
for the first one, you will need to have a parent register before ordering, but it is worth it. it's the only place i know of that sells a xenon compound.
the second one doesn't specialize in chemicals, but it also sells a variety of other things such as radioactive ore and needle sources (microscopic or smaller peices of radioactive elements that are too dangerous in large quantities placed on the tip of a needle).
Jun 29, 2008. 11:30 AMszechuan53 says:
hey, I am 14 and i make some of these chemicals.
pure hydrogen peroxide is... interesting.
:v)
Jun 28, 2008. 8:46 AMszechuan53 says:
elephant toothpaste+ballon=foamy stuff everywhere<br/>
Jan 24, 2008. 7:18 PM!Andrew_Modder! says:
lol thats cool. but it would have been cooler if you would have caught the stuff on fire xD.
Feb 23, 2008. 11:11 PMtechnodude92 says:
if you wan't flaming bubbles try pumping propane through a garden sprinkler in a bucket of soapy water. Or, if you can find it, hydrogen! since it's lighter than air, you'll have a tower of highly flammable foam!
Feb 28, 2008. 6:27 PMheavy.metal.nguyen says:
That was on Mythbusters!
Feb 28, 2008. 7:35 PMtechnodude92 says:
actually, i lied, it was methane not hydrogen. but hey! methane is easier to get than hydrogen. just hook it up to your natural gas line. i love playing with fire XD
Jun 19, 2008. 9:54 AMDerin says:
ng is not pure methane ( i lied idk)
Jun 19, 2008. 12:35 PMtechnodude92 says:
it doesn't have to be pure, but nat gas has methane and is lighter that air which is the important part
May 7, 2008. 5:56 PMmr.dr.prof.joel says:
everyones a pyromainiac except the ones who aren't.
May 8, 2008. 1:08 PMtechnodude92 says:
nobody's a pyromainac except those who are.
May 16, 2008. 2:38 PMmr.dr.prof.joel says:
touche
May 16, 2008. 7:06 PM!Andrew_Modder! says:
that'll do charlie... that'll do.
Feb 29, 2008. 4:44 PMheavy.metal.nguyen says:
I forgot haven't seen that one in months. But yeah, playing with fire is awesome.
1-40 of 54next »

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