Elephant toothpaste — safe, dramatic, unforgettable
Foam erupts out of a bottle for ten full seconds. Their reaction is the point.
How to do it
Outside, on a tarp or driveway. In a clean empty water bottle: 1/2 cup of 3% hydrogen peroxide (drugstore — for higher %, ask the pharmacist), squirt of dish soap, food coloring, swirl gently. In a small cup: one packet of dry yeast dissolved in 3 tablespoons of warm water, stirred for 30 seconds. Pour the yeast into the bottle quickly and step back. Erupting foam — warm to the touch (exothermic). Talk about what happened: the yeast acted as a catalyst, breaking peroxide rapidly into water + oxygen, the soap captured the gas as foam. Run it again with different food coloring.
What you'll need
Hydrogen peroxide 3%
AmazonActive dry yeast
AmazonDish soap
FreeFood coloring
AmazonEmpty plastic bottle
Free
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