Fun Science | Elephant's Toothpaste

I remember trying this experiment out on one of my Year 7 classes that I taught last year and it failed terribly. When I got some orders for this recently, I had flashbacks on the times it didn't work so I was adamant to make sure I get it right.

Basically, this is a chemical reaction were the products foam up and if you put it in a long tube, it rises up like toothpaste, only much bigger. This experiment is fun and easily achievable at home. Try it yourself for a neat party trick (!?!).

What you will need:

A glass or rigid clear plastic tube (I used a 500mL measuring cylinder) however

you can do a mini version of this using a soft drink bottle

150mL hydrogen peroxide (I used 30% but I think you can only get 6% or 12% at chemists)

30mL detergent

Food colouring (I used blue)

A packet of yeast mixed in some warm water

A tray to catch the reaction spill

What to do:

1. Add hydrogen peroxide and detergent into the tube/bottle and give it a gently swirl to mix.

2. Run some food colouring down the sides of the bottle for a nice effect or just into the solution.

This should look something like this. 

Mult-tasking: taking a photo and experimenting!

3. Place the bottle on a tray.

4. Add the yeast mixture to the bottle.

This reaction occurs at a moderate rate so you can be absorbed in all its chemical glory.

This is how mine turned out:

Whoa!

Oooooohh

I was a very happy little scientist at this point =D

This stuff is safe for children to touch and play with (of course don't eat it!). The mess can be wiped up and poured down the sink.

The Science:

The yeast acts a catalyst (speeds up the reaction) to break down peroxide into water and oxygen gas, making lots of bubbles. The bottle becomes warmer as heat is generated in the reaction - this is called an exothermic reaction. 

Check out this website and video for more on this experiment.

For a very explosive reaction, you can add a few potassium iodide (KI) crystals to the peroxide mixture instead of yeast. This however, forms dangerous fumes - wear gloves, safety glasses and do it outside. You don't want to play with this one.

Hope you had some fun science!

xxx Kat

Daily Katness

• I have had waaaaay too much cake the last couple of weeks!
• Did 5.6km in 42.5 mins - pretty happy with the progress.
• Not use to getting up at 5.30am for work.
• Finished reading my first Matthew Reilly book - Contest. My first adult write that I've read and I really enjoyed it. Daniel disapproves of me reading books for a younger audience - don't care!!
• Reading Temple now also by Matthew Reilly.
• I need to catch up on 4 eps of NCIS S4 that's I've taped - need more time!!
• Had a lovely time having dinner and other eatings with friends - Manjits Indian restaurant in Corrimal, Enzo Italian restaurant in Camden and Wombarra Surf Life Saving Club for a farewell tea party (more pics in a later post).

Beautiful day at Wombarra today

Such good food!