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In this video, I'm going to show you how to make crystals. For this, you will need some alum. You can get this from a chemist, or order it online. I got mine from the chemist. You'll need a spoon, piece of paper, a glass or a jam jar, some cotton, a lollipop stick, and some warm water. Right. What we need to start by doing is dissolving our crystals in our warm water. So take your warm water, get your alum crystals, just going to put some in and start stirring. Now, what you need to is stir this until all of the crystals have dissolved, and then you need to keep adding crystals until you get to a point where the crystals are no longer dissolving. What we want to make is a saturated solution, okay? So it'll take a few minutes to mix, and once you've got a few crystals at the bottom as I have now, you need to take you glass, or jam jar, and fill it up. Now, we need to create something on which our crystals are going to grow. So take your lollipop stick and some cotton, and we just need to wrap it around so you've got a bit hanging down. And then you just need to tie it. Best to do a knot, so it's nice and secure. So you've got a bit hanging down. If it's too long you can always do it into a loop, it doesn't matter what shape it is. Then we need to drop that into our solution. Just use the end of your spoon to push it down.And then you just need to leave that overnight, but covered up with our piece of paper. This stops anything from dropping in, 'cause anything that drops in will start to crystallize as well. Then, overnight, the next morning, it should look a little bit like this. As you can see, crystals have started to form on the cotton. Now, the next thing you need to do is empty the solution out of the jar that you're using, into a new jar. The reason why we do this is because crystals not only form on the cotton, but they can also form on the inside of the glass, and we really want to concentrate those crystals on the cotton. So, you empty the solution into a new glass, and you may need to make a bit more solution to just top it up - you want a full jar again. Then you pop your cotton back in the new jar, and then leave it again. You need to do that every day so eventually, after a few days, we have this whopper. There we go, our very own crystal. And that is how you make a crystal. Morag from Science Wizards demonstrates how to make you own crystals using alum, a glass or jam jar, a lollipop stick, paper, some cotton and some warm water.This is an easy, fun little science experiment. .
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