Question

purpose
the cell membrane of plant and animal cells is selectively permeable and only allows certain molecules to pass through it. this allows the cell to maintain a constant internal environment. in this lab you will study how a selectively permeable membrane works and the effects of hypertonic and hypotonic solutions. in this experiment, you will measure the diffusion of small molecules through an egg membrane by measuring the eggs mass before and after it is put into a solution.
day one:

1. obtain a plastic cup and a raw egg
2. determine the mass of the egg using a triple beam balance
3. record the mass of the egg in the table.
4. record the appearance of the egg
5. carefully place the egg in the cup. do not crack it.
6. cover the egg with vinegar
7. put plastic wrap over the cup.
8. observe what is happening and record it in the table.

prediction:
what do you think will happen to the egg after it sits in vinegar for 24 hours?

Explanation:

Vinegar contains acetic acid. The eggshell is mainly composed of calcium carbonate. When the egg is placed in vinegar, a chemical reaction occurs between acetic acid and calcium carbonate. The reaction produces carbon dioxide gas, calcium acetate, and water. As a result, the eggshell will gradually dissolve. Also, due to the selective - permeability of the egg membrane (similar to a cell membrane), water and small molecules from the vinegar may enter the egg to some extent.

Answer:

The eggshell will dissolve, and the egg may increase in size slightly as water and small molecules from the vinegar enter through the egg membrane.