Set up 1: Add a spoon of yeast+cold water leave for 10 minutes and observe the foam formation Set up 2: Add a spoon of sugar and a spoon of yeast add room temperature water leave for 10 minutes and observe the foam formation Set up 3: Add a spoon of sugar and a spoon of yeast add ice cold water and close the mouth with a plastic paper leave for 10 minutes and observe the foam formation. Measure the height of the foam formed in all the three set up. Under your finding. Give reason for your observation

The foam was found higher where the water temperatures were higher, then continued the height of the foam where the water was cold and lastly the ice water.

Explanation:

Yeasts undergo alcoholic fermentation, and perform a chemical reaction consisting of the following conditions:

That there is a substrate, that is, some reagent that the yeast can metabolize to give ethanol as a product, in this case it is sugar.

That there is a relatively anaerobic medium, that is why it is closed with film.

That the sea temperature approximately 30 degrees Celsius so that the fermentation is favored.

The bubbling that we see is nothing more than the chemical reaction that the yeast fungus produces when metabolizing the carbohydrate, which in this case is type A sugar, to give ethanol as a product. This chemical reaction releases gaseous components as fermentation occurs, that is, the more bubbling, the faster the reaction and the better the fermentation.

In the situation where the water was freezing and the foam or bubbling was lower regardless of whether it was closed by a plastic, because the extremely low temperature in the water slowed down the reaction rate of alcoholic fermentation.