Science can be seen everywhere, and it can be a lot of fun. Just take a look at today's video or another EepyBird Diet Coke® and Mentos® experiment. That's really cool! And scientific. Today's Wonder of the Day is also about liquid science, but it won't create such a big mess!
What happens when it's hot outside? You just finished your chores for the day. You mowed the lawn, raked leaves, and then picked up branches in the yard for almost two hours. You're tired…and thirsty! What better way to rest on a hot day than with a tall, cool glass of lemonade on the front porch.
You slowly sip your lemonade and relish its sweet and tangy flavor. The cold liquid cools you from the inside out. You set your glass aside and close your eyes for a few moments.
When you reach for your glass again, you notice that it's wet on the outside. Tiny drops of moisture have formed on the outside of the glass. They slowly bead and drip down like the sweat on your forehead. You knew it was hot out, but is your glass really sweating?
Not quite! It may look like sweat, but that's water on the outside of your glass of lemonade. But how did it get there? Did it just magically appear out of thin air?
Actually, it DID come right out of the air, but there's nothing magical about it. It's all science! In fact, there's a scientific name for what happened. It's called condensation.
Whether you realize it or not, there's water in the air around you all the time. Instead of liquid water, it's a gas called water vapor. Warmer air can hold much more water vapor than colder air.
When water vapor in the air comes into contact with something cool, such as the outside of a cold glass of lemonade, its molecules slow down and get closer together. When that happens, the gaseous water vapor turns back into liquid water droplets. That's condensation!
If you wear glasses, you may have noticed condensation in another form. If you've been wearing your glasses inside where it's cool and suddenly walk outside where it's warm, you may have noticed your glasses fog up. This is the result of the water vapor in the hot outside air suddenly condensing on your cooler glasses.
Particularly during fall and spring, when temperatures vary more than at other times of the year, you may notice condensation on the walls or windows of your house. You can also see it on the windows of your car. These are all examples of the same scientific process of condensation.