Question

How can you remove the hard calcium carbonate layer of the egg without damaging its semipermeable membrane? Can this egg be inserted into a bottle with a narrow neck without distorting its shape? Explain the process involved.

Answer 1

Process of removal of hard calcium carbonate of the egg

• Place the egg in a mineral acid solution. After some time (around 2 hours), the outer shell of the egg dissolves.
• If some portion of the outer shell is left undissolved, carefully remove it with your fingers.

Insertion of the egg into a bottle with a narrow neck

The egg can be inserted into a bottle with a narrow neck without distorting its shape. The processes involved are:

• Place the egg in a saturated solution (hypertonic) of sodium chloride for about 3 hours. The egg shrivels in size due to osmosis.
• Insert the egg in a bottle with a narrow neck.
• Add water to the bottle. Water will act as a hypotonic solution, and the egg regains its shape due to osmosis