Independent Expirement: Elephant Toothpaste
Elephant Toothpaste Experiment
A Decomposition of Hydrogen Peroxide
Elephant toothpaste is a toothpaste-like foam that is created by combining Potassium Iodide and Hydrogen Peroxide. The elephant toothpaste experiment demonstrates the decomposition of Hydrogen Peroxide. Decomposition is when a molecule splits into two or more simpler compounds. In this experiment, Hydrogen Peroxide separates into water and an oxygen molecule, creating a foam with the detergent. Potassium Iodide is very reactive with oxidizing agents, like Hydrogen Peroxide, making our experiment able to work. Potassium Iodide acts as a catalyst in the decomposition of Hydrogen Peroxide.
For this project, we started looking at fun experiments as soon as we could. We found some very cool experiments, but the reason why we picked this one was because the very first video we looked at of this experiment was so amazing. We thought other videos would not be as cool, but as we kept researching on elephant toothpaste videos, each one was cooler then the next, which then got us to really want to do this experiment.
Materials - 30% Hydrogen Peroxide (20 ml per flask)
Dish Soap (a few squirts or 10- 15 ml per flask)
2M Potassium Iodide (5 ml per flask)
500 ml flask
5 L flasks (2)
150 ml Flask
Prepare erlenmeyer flasks by rinsing with water and drying thoroughly. Prepare 2M Potassium Iodide solution in a separate container. Add 6.36 g of Potassium iodide to 20 ml of water. Put aside.
Outside, preferably on a grassy area, prepare a tarp.
Set 5 L erlenmeyer flasks on the tarp. In each, pour about 20 ml of Hydrogen Peroxide. Add about a squirt (10- 15 ml) of dish soap and a few drops of food coloring. Swirl to mix.
The next part of the reaction takes place almost instantly, so be ready to step back. Pour the 5 ml of the Potassium Iodide solution into the Erlenmeyer flask of Hydrogen Peroxide and soap. Observe.
Dispose tarps and wash glassware using gloves.
30% Hydrogen Peroxide can burn skin- handle with gloves. Repeated or prolonged exposure to the substance can produce target organs damage.
If it gets on skin or in eyes, flush right away with running water.
Slightly hazardous in case of skin contact, eye contact, ingestion and inhalation. Wear gloves at all times.
Reactive with oxidizing agents (like Hydrogen Peroxide)
Can stain skin and clothes.
Elephant Toothpaste is a messy foam substance as the result of the decomposition of Hydrogen Peroxide. We anticipate that 5ml of the Potassium Iodide will react quickly to 20 ml of the 30% Hydrogen Peroxide and dish soap. A rapid expansion of foam will most likely occur. The Elephant Toothpaste experiment will be documented with a video camera from a distance. We will also prepare to collect information by observing and taking notes in our journals.
During the reaction, we video taped. Below are some stills provided.
First we prepared a 2M Potassium Iodide solution by putting 6.34 g of Potassium Iodide into 20 ml of water. Because we did this step two days prior, when we acquired the Potassium Iodide solution, it had a slight yellow tint.
After preparing two 2000 ml erlenmeyer flasks with a few squirts of dish soap, we poured about 50 ml of 12% Hydrogen peroxide into each erlenmeyer flask.
After setting both flasks on a crate outside, we prepared to add 10 ml of Potassium Iodide to each flask. We poured about 10 ml of the Potassium Iodide solution into 25 ml flasks.
Initially, when we added the Potassium Iodide an instant color change and slight foaming occurred. We anticipated the reaction to take place faster, but because we used 12% Hydrogen Peroxide, the reaction was not as instant.
After swirling the flasks, the reaction began to take place.
Slowly, a thick foam oozed out the top of the flasks, resembling toothpaste. It continued to produce foam for about 8 minutes.
The quantity of foam that came out appeared to be about three times the amount of what the flask could contain.
After about eight minutes, we noticed that the foam was not as thick anymore. Slowly the foam stopped oozing out of the top.
After we saw that it would not be producing anymore foam, we dumped out the remaining contents into the sink. What came out was a clear liquid. We are assuming that that is left over Hydrogen Peroxide that did not react.
The bottom and sides of the empty containers had a yellow/brown tint. We also found this yellow/brown stain on our gloves. We believe this is from the potassium iodide.
After watching many youtube videos of this ‘Elephant Toothpaste’ experiment, we had high hopes and anticipation for an explosive reaction. We were only able to get 12% Hydrogen Peroxide, as opposed to the 30% that was suggested on the websites and in videos we saw. We thought we could try to compromise this by adding more Hydrogen Peroxide (we used 50 ml as opposed to the suggested 20 ml), but our initial reaction was still slightly disappointing. It took a few swirls to provoke the catalyst in the reaction started.
To improve this experiment, we definitely suggest using a higher concentration of Hydrogen Peroxide. Also, to take extra precaution, wear gloves and a lab coat. Although we were wearing gloves, we found parts of our hands stained yellow.