Eggshells are made up or 95% of calcium carbonate witch is the same stuff that chalk and seashells are made of. The remaining 5% includes calcium phosphate and magnesium carbonate. Eggs are formed in the reproductive system of birds, forming a protective layer, taking almost 20 hours to form! When a hen lays an egg, there is a small pocket of air formed inside the egg. Just after the egg is laid it cools causing the content of the egg to contract.
When you submerge an egg in vinegar, the shell dissolves. Vinegar contains acetic acid, which breaks apart the solid calcium carbonate crystals that make up the eggshell into their calcium and carbonate parts. The acetic acid reacts with the calcium carbonate in the eggshell and releases carbon dioxide gas that you see as bubbles on the shell.
My hypothesis is that the solution with the most amount of vinegar will dissolve the eggshells the fastest. I base my hypothesis on how acidic the solution is if it has more vinegar or more water
3 large eggs
3 glass jars
1. Put 1 cup of vinegar in a jar
2. Put 1/2 cup of water and1/2 cup of vinegar in another jar
3. Put 3/4 water and 1/4 cup of vinegar in a jar
4.Place 1 egg in each solution
5. Let the eggs sit in the solution for 6 days
IV:How much vinegar and water
DV: how long they are in the solution
CV: constant temp.
CV: only use white eggs
My hypothesis was to see which solution dissolves eggshells the best. The results indicate that this hypothesis should be considered by using different liquids. Based on the results of this experiment the all vinegar solution dissolved the eggshells the best. If I were to conduct this science fair project again I would also use lemon juice.