5 Easy At Home Science Experiments w Mark Rober

Today we're going to do five at home experiments that are very near and dear to my heart. And for the first time ever, we're sharing the recipe for our favorite bit of chemistry called ELEPHANT'S TOOTHPASTE. WE'VE GOT SOME EPIC science lined up and the coolest thing is that all of them can be easily done at home yourself. Whoa. Whoa, Bob. Whoa. First up is my childhood favorite, the egg in bottle experiment. All right, Science Bob Pflugfelder. did this at the science fair when was in first grade. And the The main reason liked it is cuz it involved fire and was allowed to light things on fire then. I'm impressed. The ingredients for this experiment are very simple. We have an egg that's peeled, hard-boiled. Just like standard milk bottle you could order off the internet. The neck size is very important now. You want it to be just smaller than an egg. How do you get the egg into this jar? Because as you can see, you can't really work. It breaks the egg. could have been mistaken. There we go. How do you get an egg into this jar without breaking the egg and making mess like this? What's the secret? Bob, is fire. First off, goggle up for safety. I'm going to grab these papers with tongs. I'm going to light the paper, put it in the jar, put the egg on top. Look at that. fully intact, non-broken egg is now inside this jar. When air heats up, the molecules want to stretch out. They're moving around lot. So when we light that fire, the air inside, it wants to stretch out. But as the flame goes out, that air starts to cool down. And all the air molecules kind of suck back together, and it just pulls the egg right back into the jar. So now the question is, Bob, how do we get this out? to go from vacuum to pressure. We just blow into this jar, And there's our egg. We should add variable. variable is something that you change. We have water balloon. It's significantly bigger than the opening. Again, if you're using fire, adult supervision is definitely required. Okay, that should get nice and hot. Now your challenge is to get that out, Bob. That's all we get. say we got one bigger. There we go. There it is. There's the bloop bloop. boy. boy. Come on. It's cooling. Wow. Man, we're getting so close. And we can't push it in either. No. We tried. Well, wait. Well, can we? That's even cooler. So that shows you just how much this air shrinks and expands when it gets hot, right? It's good start, Bob. Next up is Bob's favorite experiment, slime. And here's why. Here is picture of me at 7 years old making my first ever batch of slime. That is my evil scientist face. lot of people know how to make slime. This is old craft glue. The secret of this is chemical called polyvinyl alcohol. Now, add just little touch of water. Just going to thin that down little bit. Let's mix that up. So this is still obviously very watery. Next, I've got Borax. Now Borax you should actually find in the cleaning aisle. I'm going to take teaspoon, 5 ml, and then we're going to add about 1/2 cup of water. The nice thing about slime, everyone's slime is little bit different, right? So now we got glue and water Yep. Borax and water Yep. Also important, you want to add your color now. I'm going Jell-O pool right, Bob. love the Jell-O pool. How much of that should do? Not too much. Why? It's going to get on your hands. Your your hands will be red for the rest of the video. So you want to add it to your glue solution. Two drops? Yeah, let's start off two. I'm doing three. Don't tell Bob. heard that. Whoa, yours is looking cool. There are molecules in here and they're all loose. The Borax is going to bond all those together. You want to just kind of experiment here. I'm going to take maybe teaspoon of this and you can see right away, look. Whoa. I'm doing three. Whatever you want. I'm doing four. Don't tell Bob. Okay, but mine's like kind of goopy and runny. That means that you still don't have lot of bonds that have bonded. So you add little more of the Borax. need more bonding. This is bonding activity. So if you let it sit for just little bit of time, it makes difference, right? like how it doesn't like get on your hands. It seems like it would be sticky, but it's not. What if were to add color now? It would be very hard to mix in, right? Cuz all those bonds are made. Give it try. My hypothesis is that Mark's hands are going to be blue the rest of the video. Uh-oh. They might be blue the rest of the week. That is cool. It looks like blue heart. get why slime is so popular. And I'm going to go wash my hands. For at home science experiment number three, we've got fun one that's pretty simple. You just take very clean plate and just put nice little layer of water. Have you ever seen those water spiders that like glide on top of the water? The question is like why does it float on the water? Why doesn't it just sink? We're going to demonstrate that little bit while just pour lot of pepper. It's on the surface. It's like one of those water spiders. Okay, then you just take little bit of this blue stuff we like to call dish soap. Put wee bit of it on your finger like so. Put it wherever you want. I'm going to go right in the center. I'm magician. am powerful wizard. Pepperus repellecus. Whoa. You're wizard, Bobby. What's happening here is dish soap has this special ability. It's called surfactant. Surface tension is all the top layer of molecules in the water that are all joining arms. They're hanging together. Well, soap has the special ability to break those. As soon as you put soap, it rips that apart. And then almost like rubber band, they all go to the side. And this is why dish soap is so good at cleaning things. That's what love about science. It's like magic, but it's actually real. For experiment number four, it's super easy. for this, you need clear glass and Whoa. Whoa, Bob. Whoa. So this is seltzer water. Put couple of raisins in here and you see how immediately we got bubbles released, right? All right, now put some of these popcorn kernels So far, Bob, I'm not going to lie, this is kind of boring experiment. It's kind of lame. get it. Now, We have our dancing corn. They float. Okay, they float. BUT THEN WAIT, WHAT? What is going on? So clearly the bubbles that nucleate on it from the carbon dioxide, that's like arm floaties that are going to float you to the top. And then when it gets exposed to air, the arm floaties get popped, they sink, they get more arm floaties, they go to the top. So figured let's add variable. Let's do it in something taller, right? think there's no way corn kernel will all the way to the bottom. Okay, I'm dumping all these in with my blue hands, which someone didn't WARN ME ABOUT. WHOA, IT'S LIKE RACE to the top. okay, halfway. Three quarters. go. Yeah, we hit the bottom. This is actually way more impressive in tall cylinder. This is like corn lava lamp. Get out of here, Bob. know if it's going to work. haven't tried this. My hypothesis is that we're going to get one that goes all the way down. don't think it will. Go. Go. Go. Go. Go. Go. No. No. Come on, you got this. go. GO. GO. NO. WE'RE GETTING CLOSER, DUDE. WE'RE GETTING CLOSE. YES. This is what experimentation in science looks and feels like, you guys. We're just thinking of these things on the fly. We're curious, we're asking questions, and we answer the questions. One question we had was which of the three containers would keep the corn moving the longest. And spoiler alert, it was the biggest one, which had the most liquid and therefore the most carbon dioxide or bubbles stored up in the water. It's time for experiment number five. Bob, what is it? Elephant's toothpaste. You guessed it. And this is an experiment, just like all these, that you should definitely be doing with parent or some kind of adult. So let's start with our hydrogen peroxide. We're going to use 6 oz. you to get 3 Tbsp of warm water. Here we go. To that, we're going to add 1 Tbsp of the dry yeast. Okay. Now, I'm going to have you mix that up. Okay. It's little like hydrophobic, meaning it doesn't mix well with water unless you really try. So while we let that kind of mix little bit, Okay. I'm going to go with good squirt of our dish soap, maybe like tablespoon. And finally, some color. Classic red. Okay, so let's review. In here, we have our hydrogen peroxide, liquid soap, and we have our coloring. Yes. And here, we've got our yeast and warm water. And then the last step is to mix them together. Now this is going to act as catalyst. Going to speed up reaction that's already happening. There we go. Okay, ready? Ready. Pouring, pouring, pouring, pouring. Whoa, here it comes, Bob. Wow, it's so smooth. It looks delicious. that's so beautiful. Whenever smell this, it brings back so many fun memories. Yeah, nerd hug. Spent lot of time with this thing. In fact, for the first elephant's toothpaste we did in the pool, we ran so many experiments trying to get the right combinations. And we just weren't getting as much volume as wanted. So called up Science Bob. Tell me exactly what you're doing and you weren't using warm water. It's the warm water that we weren't considering. Why do you think warm water does the trick? The formula for water is H2O. All right, so here's my little model. So this is your and that's your two Os. Right. So you got H2O. Got it. With hydrogen peroxide, it's H2O2. Mhm. And so we add catalyst and catalyst tears the extra apart. It hugs up with one of the other Os that pulled apart and now we've got oxygen. Mhm. And water. This is why you want the right amount of catalyst to pull these off. If you don't have enough, maybe only half of the hydrogen peroxide molecules get ripped off like this, right? So many experiments. All right, so that was the at home version. Now this is 30%, which is why we have got our goggles on, we have got our gloves on. And for the first time ever, I'll say while Bob pours this in, in the video description, we are putting the recipe for this version of elephant's toothpaste. The trick is you got to do it with science teacher cuz only science teacher will be able to get this 30% hydrogen peroxide. Plus, it is more dangerous, so You don't want to do it in your kitchen. Or your bedroom. What in the world? That's my office. Okay, great. 3 Tbsp. Now we have soapy hydrogen peroxide. In honor of elephant toothpaste 3.0, say we do green. Believe that got us Guinness World Record. And now our catalyst is no longer yeast. Yes. We're using chemical called potassium iodide. Your science teacher will get easy access to it. We saw the home version. Let's do the television version. Television version. Here we go. I'm going to give you the honors. There it is. Can you STEP BACK? WOO! WE HAD DISCUSSED MOVING IT AWAY from the camera. Here we go. Uh-oh. Bob. That's big one. Whoa. It is definitely warm. Yes, this is an exothermic reaction, which means it gives off heat. Definitely don't want to touch this foam. Yeah. And you also notice that it's got these brown highlights. What's up with that? So that's the iodine from the potassium iodide. Which is brown. Let's add one more variable just to see what happens. Okay. First in three. Again, we're just adding variable. And ideally you just change one variable. In science the reason you change just one variable is now if the result is different, you know it's because of that variable. If you change three at time, the result will be different, you don't know which caused it. If this looks different, we know it's because of the container. We are using blue food coloring cuz we haven't used blue yet. Same catalyst, same amount. And it goes. was not expecting that. Wow. It just plopped out, Bob. And lovely blue color. We got our gloves on, but it's still hot. can feel the heat on that. It was yeah, that's really warm. Even through the gloves you can feel the warmth. So even if you do home version, find variable and experiment. And change it and get it to look as cool as possible. The most important words in science aren't eureka, it's that's interesting. Cuz you do something you're like, "Whoa, wasn't expecting that." So let us know in the comments what experiments you want to see us do next. If you try them yourself, of course tag us on our socials at CrunchLabs. We'll catch you next time right here at CrunchLabs.