What it shows
Yeast feeds on sugar and gives off carbon dioxide gas, which inflates a balloon fastest in warm water. Cold slows the yeast down and very hot water kills it.
This idea has a short entry only. For the science behind it, read the sentence above with your textbook and ask your teacher to explain the law or idea it shows, so you can describe it in your own words.
Materials
- Dry yeast and sugar
- Three bottles and three balloons
- Cold, warm and hot water
- A thermometer, and a tape to measure the balloons
Safety
For this project: An adult should handle the hot water.
Never use mains electricity: power models with cells, batteries or a low-voltage adapter. Sharp and hot tools, flames and lab chemicals need an adult or your teacher beside you. Keep magnets, button cells and small parts away from young children, and wash your hands after making.
All the safety rulesHow to go about it
Numbered steps have not been written for this idea yet. Plan it with your teacher: sketch the design with measurements, build one part at a time, test each part, and write every observation with the date. The free ebooks below have step-by-step projects of the same kind.
Free ebooks for this project
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