Easy⏱ time30 min$ cost3
Yeast & Sugar Balloon
Living yeast eats sugar and inflates a balloon with the gas it breathes out.
Start building ↓
Result first
The build
Step 01
Wake the yeast
Mix yeast and sugar in warm water in a bottle.
Step 02
Cap with balloon
Stretch a balloon over the bottle neck.
Step 03
Keep it warm
Set it somewhere warm.
Step 04
Watch it inflate
The balloon fills as gas builds.
Working Principle
Yeast ferments sugar and releases carbon-dioxide gas; trapped in the bottle, that gas inflates the balloon.
The science behind it
A closer look
Fermentation is respiration without oxygen; warmth speeds the yeast's metabolism and gas output.
Take it further
Variables to test
- 1 Vary the temperature — which inflates fastest?
- 2 More sugar — bigger balloon, or a limit?
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