Summary Remove the shell from an egg with a chemical reaction Science content Chemistry: Atoms, Molecules (3-7) Chemistry: Chemical Changes (2, 7) Materials egg vinegar mug or glass jar Procedure Submerge an uncooked egg in vinegar, and place in a safe place on a counter or shelf. Wait a few days to a week. Look at periodically to follow the changes. The shell will bubble as the vinegar reacts with the calcium carbonate in the shell, releasing carbon dioxide gas: CaCO3 (calcium carbonate of the shell) + 2 CH3COOH (acetic acid of vinegar) -> Ca(CH3COO)2 + H2O (water) + CO2 (carbon dioxide gas) The hard shell reacts away completely, leaving the egg surrounded just by the membranes. The egg is soft, but still intact. The membranes prevent bacteria from reaching a developing chick inside the egg, and stop moisture from leaving too fast and allow air and other gases to pass. Grades taught Gr 3 Gr 5
