Ooey! Gooey!

Another theme that occurs in movies can best be described as "GOO"! Sometimes it's cute, like Flubber; at other times, it's very scary, as in The Blob. You can make some stuff that's very much like flubbery!

What you'll need:
Blue gel glue
Borax (from the laundry aisle in the supermarket)
Water
Measuring cup
Microwave oven
Microwave-safe bowl
Mixing bowl
Spoon

Mix about 1 tablespoon of borax with 1 cup of water (these measurements don't have to be very exact) in a microwave-safe bowl and heat in the microwave oven until the water boils and most, if not all, of the borax dissolves. Let the solution cool. Squeeze the gel glue out into the other bowl. Estimate how much glue is in the bowl, and add three times that volume in water. For example, if there is about 1/4 cup of glue, add 3/4 cups of water. Now add about a volume of borax solution that is about 1/3 of that of the glue solution. In the example above, you have 1 cup of glue solution (1/4 cup glue + 3/4 cup water), and you would add 1/3 cups of borax solution. Mix with a spoon. What do you see?

The glue and borax react to form a blob of jelly-like stuff. Lift it out of the bowl and play with it. See if it bounces. Squeeze it; does it run through your finger? The molecules in the glue are long and stringy. The molecules in the borax solution tie these strings together and change their consistency. A material like this is called a gel. Can you think of any other gels?

Your goo will be good for a few days. Make sure that no one eats it, and keep it away from painted surfaces. You can make fancier goo by adding glitter or a little glow-in-the-dark paint to the glue solution before adding the borax. You can also try changing the recipe (add only 1/4 the amount of borax, or add 1/2 of the amount); how does this change the way the goo feels?

Cran-tastic Sauce!

Do you like to eat cranberry sauce on Thanksgiving? Here's an easy recipe that also teaches you something about a molecule called pectin. Be sure to do this with an adult. But best of all, it's an experiment you can eat when you're done!

Pectin is a polysaccharide, a long-chain molecule that is made up of sugar units - a sugar chain. Pectin dissolves in water, but it thickens the liquid. It's what's commonly used to make jam and jelly thick and spreadable. Pectin is found in many fruits, such as cranberries.

What you'll need:
4 cups (1 pound) of fresh cranberries
2 cups sugar
1 1/2 cups water
Deep pan for cooking
Spoon with a long handle

Wash the cranberries, picking out any that aren't red, or any leaves or other bits of plants. Mix the water and sugar and boil. Keep heating over medium until the solution turns clear. Add the cranberries and turn up the heat to high. Make sure that your pan is deep enough that the cranberry sauce won't spatter out. Watch the berries as they cook, but don't get too close to the hot mixture! Keep stirring, and notice how the cranberry sauce feels. After about 5-10 minutes, the sauce will start to thicken up, and the pectin molecules dissolves out of the berries. Cook just a few minutes more, then let the sauce cool. Store in the refrigerator, then eat within a few days. Enjoy!