Author Archives: Dan Science
A very cool experiment that I do is a demonstration of the properties of different gases. The air around you is actually made up of a number of gases mixed together, and we use the oxygen in it when we breathe – it is 78% nitrogen, 21% oxygen, and 1% other gases (mostly argon and water vapor). As you can see, air is actually made up of mostly nitrogen, a mostly unreactive, or inert, gas. There are lots of other gases, though, and a few of them have some really exciting properties.
Most people are very familiar with glow sticks – we see them all the time around holidays like Halloween or Independence Day! Even so, glow sticks are still amazing to see in action. They create a soft light of just about any color that lasts for hours or days, and do this without producing any heat whatsoever (unlike electric light bulbs, which get super hot!). We create a glow stick reaction during our show that is super bright but doesn’t last very long, and do a neat experiment by mixing two different colors to see what happens.
Way back in 2011, I posted about a neat color change experiment called The Chemical Chameleon. Nowadays, we do a different demonstration in its place called the Chemical Traffic Light. This one is great for presentation because it is actually repeatable, which is pretty rare in chemistry!
In this experiment you will build your own cold lava lamp! Regular (hot) lava lamps work by heating up wax inside a glass bottle that also has water in it. The hot wax expands a little and becomes less dense than the water, so it floats to the top in large blobs. When it cools back down, it becomes denser and sinks back to the bottom to be heated up again. You can recreate this same effect at home using a different principle and easy-to-find materials!
Chemicals often come in bottles or packages labeled with very important safety information summarized in a symbol called the “Fire Diamond.” This picture shows at a glance the type and severity of the risks that a hazardous chemical presents.
This has to be my favorite experiment I’ve done so far! The Barking Dog is a really exciting demonstration of a combustion reaction, or a chemical reaction where one material burns in another. This demonstration very beautifully brings together many of the other topics Bill and I talk about in the show, like energy, light, sound, and color!
Sometimes I like to play a little trick on my brother, who doesn’t know anything about chemistry, and get him to mix some chemicals together for me. After getting him to put on some safety gear (gloves and goggles), I tell him to mix two different chemicals together for me. Usually he does it wrong (on purpose probably), but that’s where the trick comes in. If you put too much of one into the other, it almost explodes with tons of foam and steam! It’s a bonus if he gets foam on him, but usually he gets out of the way in time.
One of the demonstrations we do in our show is the classic chemistry experiment called the Chemical Chameleon. This is a color changing reaction that proceeds on its own through a number of different beautiful colors, and involves some really interesting chemistry.