Step 2: Place egg in jar
I slid the egg in and then tilted the jar upright.
Step 3: Add Vinegar to jar
Pour enough vinegar so that the egg is completely coverd.
Step 4: Shell Starts to Dissolves
The vinegar contains acetic acid. The acetic acid in the vinegar reacts with the calcium carbonate crystals, which is what the egg shell is made of. The acetic acid causes the calcium carbonate cyrstals (the egg shell) to break into their calcium and carbonate parts. The calicum floats free and the carbonate combines with oxygen to form carbon dioxide, which are the bubbles you see forming on the shell.
Step 5: Replace Vinegar
After about 24 hours has passed you should replace the vinegar.
Carefully pour out the vinegar.
Once all of the old vinegar is removed pour in new vinegar so that again, the egg is completely cover.
As you can see in my picture I did not bother removing all of the foam, you can if you want too.
You will be able to observe that the shell is thining and patches of yellow (the yolk) will be seen through the thinning egg shell.
Step 6: Shell is dissolved
Once the shell is completely dissolved pour out the vinegar and remove the egg from the jar.