...always lacked during my school years were cool chemistry experiments.

It's true, the teachers tried to knock in our heads everything about every possible topic, but let's face it, sometimes seeing a cool experiment will teach you a lot more than just hearing about it.
So, since I tend to end up quite often on THAT part of YouTube, I thought that I would share with you my favorite chemistry experiments (but don't ask me what is actually happening, because I'm too dumb for this kind of stuff). 

1. Chlorine and Sodium 

The experiment looks quite nice and simple, but I bet that there's a whole lot of science behind something like this. What you must know for this is that sodium is highly combustible, and if you add water to it, it can even explode. As the video explains, the glass is filled with chlorine gas (and if you combine sodium and chlorine, you get...salt. For all you "Alchemy" and "Doodle God" fans) 

2. Magnetic Levitation 

Combining physics with chemistry sometimes gets some cool effects. What happens in this video is called the Meissner effect, which basically means that if you cool down superconductors, they will become diamagnetic. Something that's diamagnetic will be repulsed from a magnetic field - which is a pretty useful thing to find out, cause it lead to the concept of frictionless transportation. In the future when you will see a train "floating" above the ground instead of rolling around, you'll have to think about this. (Btw, if you were wondering where is the chemistry part of this... you would need liquid nitrogen to cool down the superconductor. That's the stuff you see in the video) 

3. Sulfur Hexafluoride

This awesome gas is colorless, odorless, non-flammable and non-toxic. But it's pretty special, because  it is more than 5 times denser than air, which will let you pour it inside a tank. It can also be used for other "fun" things, like breathing it in - it will have the exact opposite effect than Helium: it will lower your voice to unimaginable levels. This happens, because the weight of the gas slows down the sound waves produced when you are talking. The opposite happens when you inhale Helium. 

4. Superfluid Helium 

This experiment is what actually made me write this post. I happened on a superfluid helium video sometime in the past, and though this is not the same one, it basically says everything that's needed about the topic. Superfluid Helium is basically cooled down helium. When Helium cools down to -270 C, it will become a "fluid", but with a practically immeasurable viscosity, because it will pour out of practically anything. No, the glass container doesn't have holes in it - at least not ones that would be enough for water to get trough it. But Superfluid Helium is the weird kid on the block, and he does what he wants. 

5. Elephant toothpaste 

This is concentrated hydrogen peroxide mixed with dial soap and sodium iodide. Don't ask me where you get those stuff from, or how you make it - I have absolutely no idea - but whatever happens here is pretty cool. The reaction is apparently exothermic, tho, as the guys demonstrate by shaking the hot suds off their hands. I guess they aren't too far away from me in knowledge level when it comes to chemistry. Though, in case you want to learn more about it, here's a link.