Elephant Toothpaste
A catalyst makes hydrogen peroxide erupt in a giant foam column in seconds.
Start building ↓The build
Mix the catalyst
Stir yeast into warm water and let it activate.
Prep the bottle
Add peroxide, soap and colouring to a bottle on a tray.
Add the yeast
Pour the yeast mixture in fast.
Stand back
Foam surges out like toothpaste from a tube.
Yeast's catalase enzyme rapidly breaks hydrogen peroxide into water and oxygen; the soap traps the oxygen as a fast-growing foam.
A closer look
A catalyst speeds the decomposition without being consumed; the warmth you feel shows the reaction is exothermic.
Variables to test
- 1 Compare yeast vs potassium iodide as catalysts.
- 2 Vary peroxide concentration — how does foam height change?
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