Wednesday, September 26, 2012


Today I taught Batman all about density.

Density is defined as how closely packed particles are in a liquid or in an object.

First we pretended like we were going on a trip and had to pack our suitcase. We put as many clothes in the case until we couldn't fit one more thing in.   We talked about how dense (closely packed) the clothes were in the suitcase.

Now on to the fun stuff....LIQUID RAINBOWS!

This is what you'll need:

1/2 cup light corn syrup
1/2 cup blue dish soap
1/2 cup water
1/2 cup olive oil
1/2 cup rubbing alcohol
3 plastic cups
1 quart jar or glass
red, blue, and green food coloring

Pour 1/2 cup corn syrup into a cup.  Stir in 1 drop each of red and blue food coloring.  Pour the purple corn syrup into the glass jar.   

Next, slowly pour 1/2 cup blue dish soap into the glass jar.

Pour 1/2 cup water into another cup.   Stir in 2 drops of green food coloring.  Tilt the jar and very slowly pour the green water along the inside of the jar. 

Next, slowly pour 1/2 cup olive oil into the jar.

In another cup, stir 2 drops of red food coloring into 1/2 cup rubbing alcohol.    Tilt the glass jar and very slowly pour in the rubbing alcohol.

YEAH!  How cool is this?

Liquids are made up of very tiny particles.  How tightly packed these particles are determine the overall density.   Dish soap floats on corn syrup because the soap is less dense.

The reason why we carefully poured the water in so it wouldn't mix with the soap.  What is less dense then dish soap?  The water floated on top!

Not all liquids can mix.  The oil didn't mix with the water.



  1. I love this!!!!!!!

  2. Awesome density lesson!
    Thanks for sharing. My boys REALLY want to do this...I had pinned something like this from Pinterest and had meant to try it out, but when they saw the photos of your family doing this, they have made sure that we will try it out this week.
    So thanks so much for putting the ingredients and the hptos of your family enjoying this science activity.