 Welcome back to Kids Fun Science. My name is Ken. Today's experiment is how disappearing ink works. As always, adult supervision is required. What you need for this experiment, of course, a bottle of disappearing ink, a clear plastic cup, celtic water, and ammonia. A couple safety precautions. Disappearing ink and ammonia are toxic if ingested. Do not inhale ammonia fumes and do this in a well ventilated area. So you need to start off with a regular white t-shirt. I have an extra one from the runner park fishing derby here in our town. It's a fishing derby I run. So if you're in the area in the May timeframe, stop by and join our kids fishing derby. Then you need to take your magic disappearing ink and squirt it onto the shirt. And at that point, you think you've ruined the shirt as the prank is going good. The person is upset as their nice white shirt is destroyed. But you will see as a magic trick is or a prank it started off with that the science behind it that I'll explain later, the ink starts to disappear on its own. And eventually, you're not going to have any ink stain at all on your white t-shirt, which is pretty impressive. And this is a little bit of fast forward video here. So it took a little bit longer than I'm showing you. But overall, the shirt has no stain on it at the end. And I'm going to show you the science behind this show this how this works. I'm going to do it two different times. The first time I'm going to show you how I set it up and how it goes through. And the second time I will explain the science behind it. So you take your magical disappearing ink and you pour it into a plastic cup as I'm doing right here. It doesn't have to be completely full just enough so you can see that it's a purple color. And it's in your cup. So we'll bring that a little closer so you can see it. Then we're going to take seltzer water. Remember it's carbonated. So when you do open it up, it will start to bubble up. So open slowly or over a sink. And so it doesn't explode. Then you take your pipette or eyedropper and pull out some of the seltzer water and then put that into the magical disappearing ink. And you can see almost instantaneously that it starts to clear up. And I'll give it a little swirl and twist around. And it is doing exactly what it did in the shirt. It starts to have the purple color come out of the disappearing ink like magic, right? So but there is science behind it. And so but the cool thing is we can make it become disappearing ink again by adding ammonia back into this plain color here. So we take once again, we're going to take the pipette and we're going to take a little bit of the ammonia and we're going to squirt it in. And it starts to go right back to the dark purple disappearing ink. Add a little bit more. And you're back to this dark purple disappearing ink that you had before. So it's kind of cool that we did full cycle. We're able to take disappearing ink, make it go away with seltzer water and then bring it back with ammonia. Now remember not to inhale it. Make sure you're in a well ventilated area when you're doing this. And now I will explain the science behind it and how it works. All right. So the science behind the disappearing ink is disappearing ink is mostly water with a little bit of thymothialine indicator added. A small amount of basic substance is also added, which causes the thymothialine to turn to a deep purple color as we see here in the video. Thymothialine is a base indicator, which I stated, which turns deep purple in a base and clear in an acid. So more specifically, it begins to turn purple at a pH around greater than nine. But it's clear if the pH is lower than this. And you guys all understand that, but you kind of want to understand how does it disappear on your clothes? Well, disappearing ink becomes invisible on your clothes because the CO2 in the air reacts with the water and the solution to form a carbonic acid. This lowers the pH, turning the thymothialine colorless. And the seltzer water was added, the thymothialine turned clear because seltzer water contains carbonic acid. When ammonium was added, the carbonic acid was neutralized. This caused the thymothialine to turn purple since ammonia is the base. Disappearing ink by itself is just cool, but to actually do the experiment where you could make it disappear on your own and then make it reappear is awesome. So I hope you enjoyed this video. Remember to click thumbs up and to subscribe. And thanks for watching.