Hydrophobic experiment

Trying to demonstrate what it means for something to be hydrophobic, we mixed together water and oil in a small (2 Tbs) measuring cup. The result was a rather unimpressive separated mixture with one layer clear and the other label an unimpressively different slight yellow. We added some red food color to the mixture - still not an impressive difference between the two layers. We tried to dye the oil a different color and learned that whatever the food coloring is made of, it's either water of hydrophilic - at best, we could get little dots of color in the oil. We'll have to work on this one.

Sun-bleaching

We're starting to do some experiments using the sun. The big downside is that these tend to take awhile so they're more set-it-and-forget-it types of experiments. Our first sun experiment is sun-bleaching. Since the sun will bleach color out of construction paper (or just about anything else), we set up a sheet of bright red construction paper in a window that gets strong sunlight and put a few objects on it - the idea being that the sun will bleach all of the paper except what is under the objects and we'll end up with permanent "shadows" of the objects.

Our first attempt was thwarted by our cats, who clearly aren't big fans of science (they often try to chew on the materials for our science projects) who knocked all the objects into different places on the paper each day, giving us multiple and ill-defined "shadows." Still very exciting to see that the experiment can work! We're now clipping a key to the paper, which I hope will prevent the cats from causing more mischief.

Next up: sun dials and pin hole (construction paper) cameras.