Theory Thursday: Cloud in a Bottle

When I got home today Jake started me to tell about a science project that he watched on the "Amazing Science" DVD we are reviewing. (Look for the review in 2 weeks.)

"You take a plastic bottle and put alcohol in it, and swoosh it around, and put the cap back on. Then you use a drill or pencil or something to put a hole in the bottle. Then you pump it up with air and it goes WHOOOSH!His excitement was a little overwhelming. I knew what we were doing tonight, "Cloud in a Bottle".

It is simple really. Start with a two liter bottle, or any plastic bottle that can handle some pressure. A juice bottle perhaps. (Although I wouldn't try a milk carton.) Put about 1/2 teaspoon of rubbing alcohol in the bottle and "swoosh" it around to coat the bottle with it. Put a hole in the bottle. Now I pre-drilled a hole that fit a rubber fitting I had for our pump, but you can just make a small hole and cover it with duct tape and use a pump with a needle on it. (You know a needle for inflating a ball.) Insert pump end and inflate. We were trying to hit 25-30 psi. Once you get some pressure in it, release the pressure and WHOOOSH! You have a cloud in your bottle.

So why does it happen? I thought you might ask so I looked it up. When pressure is applied to the water in the air the molecules gather together and heat up. When the pressure is released the water molecules separate and cool. As they cool they form a cloud and if they cool further it rains. The alcohol evaporates quicker than water and releases its bond with itself quicker thus the alcohol cloud in the bottle forms quicker and with better visibilty than water would. (check this site for deeper info stevespanglerscience.com)

You may have noticed that there are no pictures in this post. That's because we did a video. Check out how much fun we had trying this out. Do you see our special guest in the background, its the new kid in school.

Now its your turn grab the supplies from the closet, bathroom, and recycle bin and give it a try.

Theory Thursday: Balloon in a Bottle

There are things that I hide from my kids:

1) Presents - I hide the obvious things like birthday and Christmas presents, but since I'm always searching the clearance racks and purchasing gifts when they're super cheap, I often have things that need to be kept hidden for up to a year. Also, sometimes I like to pick up little gifts for them and save them for a "rainy" day. It fun to spread out the surprises.

2. Mint Oreo Cookies - I admit, I don't let my kids know when they're in the house. I rarely splurge on them, and when I do, I don't want to share. I'll eat 1, maybe 2 at a time so they'll last me a while. The kids would just gobble them up without taking the time to truly enjoy them.

3) Balloons - If I have any plans for a pack of balloons, I have to keep them hidden. There's just something about kids and balloons. If they know we have them, they want to blow them up and play. They play for a while, purposely pop the balloon, and ask for another. It's a vicious cycle. I need to buy 2 packs at a time: 1 for playing; 1 for projects.

I just so happened to have a pack of balloons I brought home recently that I was able to keep away from my little ones. They certainly came in handy for this experiment they did with their daddy.

Grab your balloons, a hammer, nail, and plastic pop bottle (the bigger the better.)

 Using the nail and hammer, make a hole near the bottom of the bottle.

 When that doesn't work, switch to using a drill.

 It worked!

Dangle a balloon inside the bottle. Stretch the mouth of the balloon over the mouth of the bottle.

Then, blow up the balloon, put your finger over the nail hole, take your mouth away from the balloon, and remove your finger from the hole. 

Sit back and be amazed!

Wasn't that great?!?

Ok, it didn't exactly work as planned. In fact, it didn't work at all. It's supposed to flip the balloon inside out. The air in the bottle was pushed out the nail hole when the balloon was inflated. When you remove your thumb, air rushes back into the bottle. At the same time, air rushes out of the balloon. The combination of forces is strong enough to turn the balloon inside out. Supposedly. We never saw it. And we tried - over and over again. Leighton thought maybe the hole wasn't big enough, so air wasn't rushing back in fast enough to flip the balloon.

Don't worry, he remedied the hole situation.

Notice the balloon was red and changed to blue? Don't let a child attempt to blow up a balloon if you plan to inflate it afterward. That is unless you like slobber-covered balloons.

They tried a few more times with the bigger hole, each producing the same result - nothing. Jake said, "I don't think they tried this before putting it in the book." I don't think so either, buddy.

So, this Theory Thursday experiment was busted. (I didn't intend on the balloon pun, but it made me laugh regardless! Ha!) Either way, the kids had fun trying it. Did you hear those giggles??? Makes me smile every time. Learning isn't about always getting the result you expect, but by trying new things and observing the results. That made this experiment completely worth it.

Theory Thursday: Soy Sauce Submarine

 I don't know about you but when I was a kid I always loved playing with stuff that floated in the bathtub. I had this little wooden boat that I played with all the time. My dad had made it for me, it was just a basic boat shape cut from plywood with a dowel sticking out the middle and a piece of material that hung off the dowel as a sail. How many of us threw rocks in any body of water we had the chance to, I still do! We love playing in the water. There is something intriguing about seeing what floats and sinks. How about something that floats and sinks?

All you need is a bottle full of water, Soy sauce packet (or any plastic condiment packet), and a small paper clip or two.

Attach the paper clip to the bottom of packet and insert in the bottle.

It should float at the top of the bottle. If it floats with a lot of the package above the surface of the water add another paper clip or upgrade to a large paper clip. Do yourself a favor though, don't start with a large paper clip. It just might be too heavy and sink. Then you have dump all the water and fish the packet back out. I won't mention how I know this.

With your sauce packet now floating at the surface begin to squeeze the bottle.

Isn't that cool! So.... do you wanna know how it works? We all know that water is less dense than air that is why it "floats" above the water in the bottle. Well the air in the sauce packet keeps the packet afloat. When you squeeze the bottle the air and water have no where to go so something has to give. Since water does not compress as air does the water compresses the air. When the air inside the packet gets compressed to the point at which it is denser than the water outside the packet the packet falls. When you release your squeeze all returns to normal and the packet floats.

Well, don't just watch our video. Go make your own see how hard you have to squeeze the bottle. Can you squeeze hard enough to get the air in the packet to lay the packet down? Or can you get the packet to float in the middle? Make it a game, who can get the packet to float in the middle the longest? Just go try it and have fun!