An “Eggcellent” Experiment

eggfThis is a series of really fun experiments with nothing more than an egg, vinegar, clear corn syrup, and water.  I like to write and display the kids hypothesis’ with each step because they usually vary greatly.  In the first step of the experiment we place a raw egg with shell in a jar of vinegar.  The next morning when we gently touch the egg it is evident that the egg no longer has a shell.  Basically, vinegar is an acid.  The eggshell is made of calcium carbonate.  The vinegar dissolves the calcium carbonate.  Now when you place the egg in corn syrup after twenty four hours it looks deflated.  The reason is the egg as a thin membrane. That is why it is still looks like an egg, even if it is deflated.  Water molecules are able to pass in and out of the membrane.  The water molecules inside the egg travel to were there are less water molecules (the corn syrup).  Hence why the egg no longer looks plump.  Lastly, we place the egg in a jar of water.  After awhile we have our nice plump egg again.  Those water molecules simply moved thru the membrane and back inside the egg.