Osmosis Egg

Here's what you'll need...
  • Shell-less egg
  • cup
  • water
  • food coloring (optional)
  • corn syrup

Here is something you can do with the shell-less eggs that Kinetic Kris just showed you how to do.

Once you have removed the shell from an egg, as shown on last week’s video, here’s a fun experiment you can try, to learn more about cells and the process called osmosis.

First take the shell-less egg and place it in a glass of water so that the egg is completely submerged. An optional step is to color the water with food coloring before placing the egg into it. Let the egg sit overnight.

If you have two shell-less eggs you can do this step at the same time as the first step, however it will also work before or after the first step. Take the egg and submerge it in corn syrup. The egg will float a little bit, but as long as most of the egg is covered with corn syrup, it will still work. Once again let it sit over night.

Once the egg and liquid reach equilibrium (egg in corn syrup shrinks, and egg in water expands) feel free to switch the eggs. Take the egg soaked in water, and place it in fresh corn syrup, and the egg soaked in corn syrup and place it in the water. Let them sit overnight.

When the hard outer layer of the eggs shell is dissolved away, what is left is a rubbery soft membrane around the egg. This membrane acts the same as a single cell’s membrane because it allows for osmosis.

Osmosis is the process in which water and nutrients will travel through a membrane into or out of an area. In the example of a single cell, water and nutrients out side of the cell are allowed to travel through the membrane and into the cell while bigger things, like dust, dirt, or other impurities are not allowed to travel through the membrane and into the cell.

Water, in the process of osmosis, only travels from areas of greater concentration of water to areas of less concentration of water. This continues to happen until both sides of the membrane are in equilibrium, or there is the same amount of water on both sides of the membrane.

With our osmosis egg that was placed in the blue water, there was a higher concentration of water on the out side of the egg membrane then on the inside. Therefore, from osmosis, water and food coloring traveled from the out side of the egg to the inside.

The egg placed in corn syrup worked the exact opposite. There was a higher concentration of water on the inside of the egg then the outside. This means water traveled from inside the egg to the out side until equilibrium was reached.

This also happened when the blue, water saturated egg was placed into the corn syrup. However, instead of just water, water and blue food coloring passed through the eggs membrane into the corn syrup. That is why you can see the corn syrup turn blue.