Tuesday, August 24, 2010

A Bubbling Lava Lamp--Science Rules

abc button

Another great experiment from Steve Spangler.
It takes just some everyday products---(although I have never had Alka-Seltzers in the house before)
Our jumbo test tubes are also from Steve Spangler Science.
Fill test tube, or a soda bottle, 3/4 full of vegetable oil.
Fill up the rest of the test tube with water.
This is a great time to talk about the fact that water is more dense than the oil.
Add about 10 drops of food coloring to the test tube.
It is fun to watch the water based food coloring "float" through the oil and then mix into the water at the bottom of the test tube.
Divide the Alka-seltzer into about 8 pieces.
The reaction is great!!
The Alka-seltzer reacts with the water, forming carbon dioxide gas. The bubbles of gas rise to the surface of the tube. The gas bubble pops at the surface and then the water drops back to the bottom of the test tube.
We have been repeating this with additional pieces of Alka-seltzer all day.
It works again and again.

After our reactions settled down, the kids enjoyed using the test tubes as their own ocean wave bottles.
A whole afternoon of easy science fun!!
Check out the video of today's experiment at this post.