Science experiments for kids with salt and pepper

I found a great experiment for kids at tryscience.org that has to do with surface tension. I did this experiment in the 6^th grade, so it was fun to find it explained here.

You will need; water, salt, pepper, and soap.

To do this experiment you will need to fill a bowl with water. Next you will add the salt and pepper. The pepper is easier to see. You will notice that the salt and pepper will float on the top of the water. Last you will need to touch the top of the water with the soap. This will make the salt and pepper move quickly to the sides of the bowl, away from the soap.

Why is this happening? The web site explains it like this “Surface tension on water makes a strong 'skin' which is tight and not very elastic. The pepper stays on the water until soap or detergent touches the skin. Soap and detergent reduce the attractive forces between water molecules--that is, they reduce surface tension. The skin stretches, scattering the pepper.”

I also understood that there is a chemical reaction that makes the salt and pepper run away.

Click here if you are looking for more science experiments for kids.

What do you think?

Donna