Friday, December 2, 2011

Icy Ovens

I take it you have heard of the convection oven. A convenient cooking tool that makes sure the whole oven is warm. The best way to make perfect cookies!
Mmmm, gingerbread cookies! How festive!
We know you all like cookies.

To explain the idea of convection (the process that makes perfect cookies) we are going to do an experiment with ice cubes!

Materials:
- A rectangular tub about 10 inches deep
- Desk Lamp (with lightbulb)
- Ice Cube Tray
- Blue and Red Food Coloring

 

What To Do:
(Pre-Lab Set Up) - Fill an Ice Cube Tray with water; add a few drops of blue dye to each container
1. First fill the tub with about 8 inches of water.

2. Place both the tub and the lamp on a flat surface. Position the lamp over one half of the tub. Let the light sit on over the tub for 10-20 minutes.

3.) Put the ice cubes in the side of the tub opposite the lamp.

4.) Place a few drops of red food coloring on the side with the lamp.

5.) Watch the initial reaction. The food color should not mix at this point because they are different temperatures. (However some of the dye may mix, that happened with us.)

6.) After about 20 (maybe more) minutes the water should be a purple and the ice cubes melted. This is because heat from the lamp has moved throughout the container (convection!) and the food coloring has mixed.

Suggestions: When making the blue ice cubes make the water very dark blue. The dye freezes at a different rate than the water. also it will help when viewing the mixing of colors.



1 comment:

  1. Awesome experiment. Reminds me of a prof who once described convection as the ice cooling your gin and tonic causing it to sink to the bottom of the glass.

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