 Welcome back to Kids Fun Science. My name is Ken. Today's experiment is the baking powder spud marine. As always, adult supervision is required. What you need for this experiment is a potato, a dowel, a tank for water, a wood, knife, baking soda, cream a tartar, drill bit, and water. Start off with a small potato. I use a quarter inch drill bit, a six and three five millimeter drill bit, and just make three holes. I'm doing it by hand. You might have to put it into your actual drill. It seemed pretty easy. Just do it by hand. Go all the way through and pull it out so it's clean for all three and you kind of just center it out there. So you have all three completely. If you have to go back, you don't want to make the hole larger than a quarter inch, so don't make it bigger, but make sure it's clear all the way through on both sides. So we have it look exactly like this. So you can see all the way through. Then you're going to take a box cutter or a knife and on the bottom part of it, you're going to cut out like a funnel or a larger hole. So make sure you don't hit the other two holes. So when you do do the drill bits, make sure they're separated out so you don't have them too close together. And then you're just going to take this piece out and you're going to make a larger hole kind of like in a funnel shape. So you're going to continue to do that and play with it. You might even have to trim it up a little bit towards the end after we do a little bit of testing. So we'll keep carving this out and you'll see the end results. I'm going to go a little bit farther than that. Then take a thin piece of plywood and a dowel and we're going to cut them to these dimensions. The dowel is going to be a quarter inch dowel and I'm going to make that one inch or 2.5 centimeters. And then the piece of plywood is a half inch by one inch or 1.25 centimeters by two and a half centimeters. So what we're trying to do here is to kind of get baking powder. That's baking soda. So to get baking powder we need to do one teaspoon of baking soda just like this. And then we're going to do one teaspoon of cream of tartar and we're going to put that in there and then we're going to mix it up. So it's completely mixed up and then that gives you baking powder and that's what we need is baking powder, not baking soda. Even though we do use baking soda you need the cream of tartar sauce and mix that up and then we'll be a little bit more and we're ready to do the experiment. So now you're going to take your periscope, put it inside. It should fit really snug inside that plywood that we cut out and drill the hole in in the middle. And then you're going to put that on the top part of it with the longer end of the stick in there or push it all the way down. So I'm going to flip that over and push it in so it's nice and tight. And then we should go into testing our spud marine. So here it is. As you can see I got my hole in the bottom. It's a little bit bigger than the others. I cut off the sides because when you test it and put it in the water without the baking powder it should sink very very slowly and it wasn't. So I cut off just like that, that speed right there. But I cut off too much and so then it just floated, right? So I had to put some pieces back on and I used some toothpicks to be able to hold the extra pieces back on afterwards. So now we're ready to go. You put the baking powder just a little bit in there and compact it down. I just do it with my finger. And then you can see my toothpicks in there holding that extra piece of potato just to get the right weight on the potato so it sinks. And then you put it in and it will sink to the bottom and it will stay there. And then it starts to sit. It's waiting and hopefully we're going to just like a submarine. We're going to start to go back up to the surface which is pretty pretty cool. So the science behind this is the baking powder will come in contact with water which then will turn into and cause a chemical reaction. This reaction will produce air bubbles along the bottom of the potatoes as you can see right here a little stream causing it to rise back to the surface. And if we come in closer here we can see underneath all the air bubbles pop in the pocket and it's creating more as you see it fizzing right there. And it's what's causing the spud marine to come to the surface. So we put it down to the bottom and it's going to rise right back up to the top as it will keep creating air bubbles and making that chemical reaction until all the baking powder is used up. Which I find pretty fascinating. The hardest part is getting the potato to be the exact weight so it sinks but it doesn't float. And so once you get that down you'll be set. I hope you enjoyed this video. Remember to click thumbs up and to subscribe. Thanks for watching.