Before starting your science experiment, you will need several essential ingredients, including one egg either hard boiled or raw. If you feel you are accident prone, a hard boiled egg may be best. From here you need one cup of vinegar as well as a clear jar or glass to place the vinegar into and observe your experiment.
Take the cup of vinegar and pour it directly into the glass or jar. From here, add the egg to the jar, making sure it does not crack in the process. As the egg moves down to the bottom of the jar, bubbles will start to rise out of the egg. Leave the egg in the vinegar for an entire day. After a day has passed, let the egg dry before properly examining the texture of the egg shell.
After completing the experiment, you should take notes on the changes in the texture and hardness of the shell. During the chemical reaction, the vinegar reacts with the calcium carbonate in the shell of the egg. The vinegar removes the calcium from the eggs shell through the bubbles you observed in the tank. After a day, nearly all of the calcium is removed, leaving the shell soft. Acetic acid is commonly found in vinegar but can also be used in pure form or in other substances for this experiment.
After finishing the experiment, leave the egg out for an additional day. You will observe that the hardness of the egg shell has returned. After a day of exposure to the carbon dioxide in the air, the little calcium that remained in the shell of the egg will suck back in the carbon, restoring the firmness and original texture to the eggs shell. You can also leave the egg in the vinegar for an extra few days to fully dissolve the shell.