Experiments        < Previous        Next >

 

Repulsion

 

Today's Snack: Some people don't like pickles. They are "repulsed" by them. Well, what do THEY know? Even if you don't particularly like pickles, you'll like today's treat. Wrap a slice of deli ham around a dill pickle, and dip it in a dab of mustard. Balance that salty taste with a tall glass of sweet apple juice.

 

--------------------

 

Supplies:

 

Small water container, like a recycled yogurt cup

Water

Salt and pepper

Dishwashing detergent

Eyedropper or toothpick

 

 

Pour water into the yogurt cup so that it's about " from the top.

 

Shake a few shakes of salt and pepper onto the top. Be very careful not to touch or jiggle the cup. The salt and pepper should be floating on the top of the water. If it has sunk, wash out your cup and try again, making sure not to jostle or touch the cup of water once it's in place.

 

Now take a small quantity of dishwashing detergent with an eyedropper or toothpick, and drop a drop right in the middle of the water.

 

What happens? Why?

 

The soap cuts through the "surface tension" of the top of the water - air molecules that allowed the salt and pepper to float on the top.

 

The soap's molecules repel, or push away, the molecules of the salt and pepper, and they move as far away from the soap as they can get.

 

Wish it were that easy to get things we don't like to move away!

 

 

By Susan Darst Williams www.AfterSchoolTreats.com Experiments 06 2009

Experiments        < Previous        Next >

AfterSchoolTreats.com, All Rights Reserved.