Water is all around us and essential for the survival of life on Earth. It can also be a lot of fun to play with. If your teen has graduated from squirt guns to science experiments, encourage him to play around with some easy water-based chemistry experiments that will get him thinking about the world around him.
Sinkers and Floaters
It's time to solve the age-old mystery: why do some cans float and others sit at the bottom when you open a cooler filled with melted ice. Gather cans of regular and diet soda. You'll need an aquarium, sink or large cooler for the experiment. Fill the cooler almost all the way up with water. Gently put in a can of regular soda; you don't want to trap a bubble beneath it because that can affect the results. Repeat with a can of diet pop. Make a note of which cans sink and which float. The results should show that the more dense pop, the one with actual sugar, sinks to the bottom while artificially flavored diet sodas float to the top. If you have a can of beer or soup, try that as well.
In this experiment, your teen can control a diver in a bottle. She'll need a 1- or 2-liter clear plastic bottle and a small packet, like ketchup, soy sauce or a sealed Milky Way mini chocolate bar. Before starting, put the small packet in a bowl of water. She'll need a packet that barely floats so you might have to try a few before you find the perfect almost-floater. Squeeze the packet into the bottle and fill it to the top with water. Now she can squeeze the bottle. Because the packet has a small pocket of air in it, it will tend to float. When the bottle is squeezed, the air pressure inside the bottle is increased, compressing the packet's air bubble and making the packet denser than the water. This causes the packet to sink.
Bend it Like Beckham
This extremely quick and simple experiment uses only a water faucet and a nylon comb. Your teen should turn on the faucet so the stream of water is only about 1/16 an inch in diameter. Get her to comb her hair a few times. Slowly, she should move the comb toward the water, staying about 4 inches below the faucet itself. By the time the comb's teeth are an inch or less away from the water, the water will bend away toward the comb. Ask her if the distance between the water and comb changes if she moves the comb closer. If there is more or less water coming out of the tap, will that effect how the water moves? As she combs her hair, the comb becomes charged with static electricity that attracts the water.
Build Your Own Tornado
Your teen can create his own tornado using a water bottle, water, glitter and a few drops of dishwashing liquid. The water bottle needs to be about three-quarters full. Add the drops of dishwasher liquid and a few pinches of glitter. It will make it easier to see the tornado. Now he just has to turn the bottle upside down, hold it by the neck and spin it as quick as he can for a few seconds. Stop spinning and there should be a small tornado whirling in the bottle. The spinning caused a water vortex. If it doesn't appear the first time, try again. It might just need a little more spin.