 Welcome back to Kids Fun Science. My name is Ken. Today's experiment is the film canister sub powered by Alka Seltzer. As always, adult supervision is required. What you need for this experiment is a film canister, a drill, an Alka Seltzer tablet, pennies, a cylinder, and water. So start off with an adult helping you. You can take an electric drill like I'm doing and just drill a very small hole on the top cap or lid of the film canister. As you notice, I have extra film canisters because I did an experiment with rockets and Alka Seltzers. So I'm kind of playing off of accessories that I already own. Anyway, I got the small hole, pop it open, and now you got to kind of do a little bit of rocket science or figuring out how many pennies you're going to need to make the canisters sink. So I'm starting off with 10 here, but I'm going to end up needing 13. So depending if you don't have pennies, you're just going to grab a similar size coin. And you're going to test how many coins you fill it up and then put the lid on with no water in it and see if it sinks. So I'm putting in 12 here, and you can count if you don't believe me. And so I'm going to put 12 pennies in. If you don't have pennies, just pick the number of pennies you need and keep adding them until you find the right amount that will sink the canister. So I've got 12 right here. I'm going to put the lid on and put it into the water and to see what happens. And so when I do this, it floats. So now I know I'm to the point because I already know I'm going to put one more penny in and it's going to sink, hopefully. And so this is what you're going to want to do with your coins. And once you get to this point, then you're going to pull it out and you're going to remove one of the coins. Right. So take one coin out. So I'm back down to 12 now. And then what I'm going to do is fill the canister up with water, almost to the top. And then from there, I'm going to take my Alka Seltzer, which I already own. Believe it or not, I take a very small piece, put it in and clamp the lid down. I've never used Alka Seltzer for myself, which is intended. Flip the canister upside down and let it go and it'll sink to the bottom. But I've used it many, many times. I bought boxes and boxes of this stuff. You can see the Alka Seltzer tablet is working hard inside the box, inside the film canister. And it is creating gas. And so the submarine should go off in about 30 seconds. And it can be anytime now. And the film canister sub will have this ballast is filled and it should rise to the top as a normal sub will. There it goes. And it did it. So I will explain the science behind it. So the science behind this is when we add water to the canister and then we add that small piece of Alka Seltzer tablet to it, it produces a CO2 gas. And then that will force the water out of the small hole. That's why it's essential to have the hole pointed downward when we release the canister. So that way the water can be pushed out by the gas. If the hole is upward, then the gas will simply just bubble up through the hole and it won't do anything but sit on the bottom. When the water is pushed out of the canister, the canister has a mass is decreased. Since the volume of the sub remains constant, the density of the sub is therefore decreased. Now that the density has decreased, the buoyant force of the water is able to push the sub upward causing it to rise. This is how real subs operate. To sink, they take water into their ballast tanks, making the sub less dense than water. You can take this experiment a little bit farther by taking other products and combinations that produce carbon dioxide gas to see if your sub will rise. I hope you enjoyed this video. Remember to click thumbs up or to share if you like it and thanks for watching.