Yeast or Saccharomyces Cerevisiae is a microorganism that converts the household sugar into Ethanol and Carbon-dioxide. Ethanol in the whole world is made by this method. Here’s how to perform this reaction:
You will need:
1) A plastic bottle with air-tight cap. Preferably a mineral water bottle.
2) Household Sugar
3) Water
4) Yeast
Yeast is a common baking ingredient so you can easily in supermarkets.
Procedure:
1) Clean the bottle you are going to use, then fill it half with water. Make sure the water is neither hot, nor cold. Pour out the water in a glass.
2) Keep dissolving sugar in this water until it dissolves no more. This might take a little time.
3) Pour this mixture back into the bottle.
4) Put half tea-spoon of yeast in it. Put back the cap on the bottle and make sure it’s air tight.
5) Shake the bottle vigorously from side to side for half a minute.
6) Put this bottle somewhere cool in your house. Don’t put it in the fridge or refrigerator.
7) Wait 24-36 hours until the reaction has completed.
8) Uncapping the bottle will release all the Carbon-dioxide. If you want to save it for later, you can put it in a fridge.
Advanced:
Before adding yeast, put small amount of Urea and Phosphoric acid in the bottle. Urea will help increase the population of the microorganism and phosphoric acid will prevent from building up of colonies. Both of these chemicals will increase the rate of reaction and help convert maximum possible sugar.
Things to remember:
1) The microorganism will die if the temperature is too high, and it will slow down if the temperature is too low. Ideally the temperature should be anywhere from 20 degree Celsius to 30 degree Celsius.
2) Make sure the cap is air tight otherwise the Carbon-dioxide will escape.
3) Don’t fill the bottle too much. Otherwise, the Carbon-dioxide produced will increase the pressure inside the bottle too much as a result the bottle might explode.
4) Make sure the experiment is supervised by an adult. One of the products is ethanol, or common Alcohol.
5) Ethanol is highly flammable. At the end of reaction, when you are opening the bottle, make sure there is no flame nearby.
6) When storing it in fridge, it is best to first put it in a plastic and tighten the bag. In case the bottle explodes, your fridge will be a mess.
