Welcome to Providence High School. You and your family are invited to share in an osmosis lab with me, David Bird, the department chair of science.

I teach science with a holistic approach. I blend science concepts and demos to show how each concept relates to each other. Diffusion and osmosis are important concepts in biology, especially the medical sciences. We will use this demo to discuss blood, the human body, and even sports drinks.

Osmosis is the diffusion of water

When water moves from an area of high concentration to low concentration

Some words we need to know:

-Solvent (Usually water) -the substance there is more of. the liquid doing the dissolving.

-Solute-The other substance in the mixture of the solvent and the solute. Usually the stuff mixed in with water

-Hypertonic- having less water (More pressure)

-Hypotonic- having more water (Less pressure)

-Isotonic- having an even amount (Same pressure)

In this Demo we are going to observe the affects of osmosis on two eggs. Later we will make a comparison with these eggs to blood cells.

Bird eggs have a hard shell. This shell is designed to prevent water loss. In order for us to observe osmosis we will have to remove the shell (create a naked egg)

Materials Needed:

A bottle of white vinegar

A bottle of corn syrup

Eggs

Water

At least 2 glasses or containers

Time needed:

1 day with vinegar

2 more days with fresh vinegar

2 days with water or corn syrup

Total of 5 days to complete the Demo

Procedure:

Place two eggs in two different glasses (I would suggest making extra in case an egg breaks. Maybe make 3 or 4.

Fill the glasses with white vinegar

Place the glasses in the refrigerator for around 24 hours

After 24 hours pour out the vinegar in each glass and replace with fresh vinegar

Place the glasses back in the refrigerator for another 48 hours

Now your eggs have been sitting in vinegar for a total of 3 days. You should now have naked eggs.

Pour out the vinegar and place one naked egg in a glass full of just water and the other egg in a glass full of corn syrup. Place these two glasses back in the refrigerator and leave them for another 24-48 hours.

After a day or two you should now see the affects of osmosis on the two eggs.

What happened:

Osmosis is the movement of water from an area of high concentration to an area of low concentration

In the jar of just water, the glass of water was more hypotonic compared to the egg. Water goes from a hypotonic solution to a hypertonic one. In this case the egg was hypertonic to the jar of water. The water entered the membrane of the egg causing it to swell.

In the jar of corn syrup, the corn syrup was more hypertonic compared to the egg. In this case the egg was hypotonic compared to the jar of corn syrup. The water from in the egg left the membrane of the egg causing the egg to shrivel.