Raw egg




  1. Place the whole egg (with shell) into the jar
  2. Fill the jar with vinegar
  3. Place the whole egg (with shell) into the jar
  4. Leave for 24 hours
  5. Pour out the vinegar
  6. Pour fresh vinegar in and cover the egg
  7. Leave for 7 days
  8. Do not disturb the egg but pay close attention to the bubbles forming
  9. After 7 days, pour the vinegar off and carefully rinse the egg
  10. All that is left is a thin membrane surrounding the egg white and yolk


Let’s start with the bubbles you saw forming on the shell. The bubbles are carbon dioxide (CO2). Vinegar is an acid called acetic acid (CH3COOH), and white vinegar from the grocery store is usually about 4% acetic acid and 96% water. Eggshells are made up of calcium carbonate (CaCO3). The acetic acid in the vinegar reacts with the calcium carbonate in the eggshell to make calcium acetate plus water and carbon dioxide that you see as bubbles on the surface of the shell.

The chemical reaction looks like this . . .

2 CH3COOH + CaCO3 = Ca(CH3COO)2 + H2O + CO2

Acetic acid + Calcium carbonate = Calcium acetate + Water + Carbon dioxide

The egg looks translucent when you shine a flashlight through it because the hard outside shell is gone. The only part that remains is the thin membrane called a semipermeable membrane.

You might have noticed that the egg got a little bigger after soaking in the vinegar. Here’s what happened…Some of the water in the vinegar solution (remember that household vinegar is 96% water) traveled through the egg’s membrane in an effort to equalize the concentration of water on both sides of the membrane. This flow of water through a semipermeable membrane is called osmosis.

If you take your naked egg and place it in a glass filled with corn syrup, the egg will shrivel. Since corn syrup has a lower concentration of water than an egg does, the water in the egg moves through the membrane and into the corn syrup to equalize the water concentration levels on both sides.