Question

Project : Requirements – 2 test tubes, marker pen, sugar, yeast powder, 2 balloons and lime water.
Take two test tubes and mark them A and B. Clamp these tubes in a stand and fill them with water leaving some space at the top. Put two spoonfuls of sugar in each of the test tubes. Add a spoonful of yeast in test tube B. Inflate the two balloons incompletely. Now tie the balloons on the mouths of each test tube. Keep them in a warm place, away from sunlight. Watch the setup every day for next 3-4 days. Record your observations and think of an explanation.
Now take another test tube filled 1/4 with lime water. Remove the balloon from test tube B in such a manner that gas inside the balloon does not escape. Fit the balloon on the test tube and shake well. Observe and explain.

Answer 1

Answer:

This experiment is known as the Sugar Yeast Experiment,

Tube A (no sugar), Tube B (sugar)

As the yeast eats the sugar (tube B), and breaks it down to ethanol and carbon dioxide. The gas (carbon dioxide) fills the test tub and, the more sugar is added the more gas is created. The yeast used in this experiment are the related species and strains of Saccharomyces cervisiae.

When adding the lime to the test tube B, in the presence of the gas the lime water will turn milky if CO2 is introduced because of the formation of calcium carbonate."

The equation is:

Limewater + Carbon Dioxide --> Chalk + Water