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Dr. Kate Biberdorf

Dr. Kate Biberdorf is a scientist, a science entertainer, and a professor at the University of Texas. Through her theatrical and hands-on approach to teaching, Dr. Biberdorf is breaking down[…]

KATE THE CHEMIST: If you are at home and stuck with your kid you might as well do something fun and educational with them. What I've done here is put together a super, super fun science demonstration that is safe to do at home with your kids and hopefully all these ingredients you already have in your pantry or your craft drawer or something like that because I don't know about you, but I get maxed out on screen time so I think it's really fun to do something kinesthetic with your hands. And if you can learn something while you're doing it you might as well have fun too. Okay, this is called the bubble snake and I'm going to explain first the ingredients and then give you step-by-step instructions on how to do this.

First things first is you need to get a small plastic soda bottle or a water bottle. I have these little ones in my garage because I use them when I breathe fire but the bigger soda bottles or water bottles work just as well because what you're going to do with it is actually just cut it off so you have the top part of it but I'll get there in just a second. So, any size bottle will do. You need food coloring. I prefer the reds and the pinks when I'm doing this outside but because of being on camera I'm going to use greens and blues for you. You're going to need a half cup of water, a quarter cup of dish soap, a bowl to mix your dish soap and water, a spoon, one rubber band and then an old rag. You can use a sock, you can use a rag, you can use a towel, a tee shirt. Anything will really work for this. You just don't want something that's super, super porous or super thick.

The first thing you're going to do is you're going to take your plastic soda bottle or water bottle and you're going to cut off the bottom part. You only want the top portion of your soda bottle. So a perfect one is going to look like this. You're gong to see your top part here and then it's cut off right there at the edge. Then what you're going to do is take your old rag and you're going to wrap it around the edge of your soda bottle so that's where your rubber band comes into play. You're going to wrap the rubber band around your towel just like this. Two or three times should be absolutely plenty. You just want to make sure that towel sticks on here. I did this once and the rubber band snapped and the stuff went all over this actor's head because I was doing it on camera. It was an awesome day but the poor guy was covered in food coloring.

Once you have this you're going to put it off to the side and we're going to build our little concoction over here. In your bowl you need to have a quarter cup of dish soap. Any bubbles will do. Bubble bath will work if you're keeping your dish soap around for quarantine time which I totally understand. Then you've got a half cup of water so you're going to add that into your dish soap. Now you want to make sure that you stir this together so completely stir. And I would stir for at least 10 or 15 seconds. I'm not going to do that for you here but make sure you stir for a long time because you want to make sure that your solution is super bubbly. You don't want to dip your bubble snake apparatus into just water. You want to make sure you have the soap as well. So then you're going to take this, flip it upside down so that your towel is exposed and then grab your food coloring. Now the goal is to cover your entire patch down here, the whole piece on this side. Cover they entire thing with your food coloring. I like to do stripes and zig-zags and patterns with all types of different colors, but just for the sake of time today I'm just going to use a big green blob. Not super attractive but it will work for our purpose here.

Then what I'm going to do is I'm just going to move my soap out of the way for a second here. Now is the fun part. You're going to take your apparatus. Now you're going to dunk it food coloring side down into your dish soap water bowl. When you pick it up let it drain. You're going to see that the food coloring comes off, totally normal. But if you're type A like me and you don't like lots of messes let it drain into the bowl. Now, for the fun part. Once it stops draining you're going to go from the side. Take a deep breath and you blow. And you make this incredible bubble snake. And so what you're doing is you're exhaling all of this gas that's in your lungs out so there's nitrogen molecules, oxygen, carbon dioxide, even some water in here. If you can go outside but stay within your little area six feet away from everybody, you can let the wind actually carry this bubble snake around and it is so fun. I love, love, love it.

So what I love about this experiment is it's something you can do at home with your kids. It is completely safe. There's nothing here that's dangerous at all. No explosions or fire or anything, but you're outside, you're engaged, you're having a good time, you're outside, you're engaged, you're having a good time, some family time, but you're learning as well. The kids might ask you what are the molecules that are in your exhale and you can talk about how you exhale carbon dioxide and oxygen and nitrogen. I just think it's so fun to spend some time with the family and do some science as well. So, if you're looking for other experiments you can check out my Big Book of Experiments which has 25 experiments that you can do with things that are at home hopefully in your kitchen right now.