Happy 4th!

I love fireworks. Something about them just mesmorizes me. It actually intrigues me even more now that I know how they work and what they are. All the little pieces that go into making one small shell to get an "ooh" or an "ahh" out of a crowd. If you wish to be kept in the dark, then you might want to skip this entry in hopes of keeping the mystery alive still. If you are interested, don't expect rocket science here...although the only difference in the two is the oxidizing agent for color...but that's another story. This will be kept on the level I teach my chemistry kids. We do a fireworks lab in my class to help them name the different chemical compounds in fireworks. The colors they give off during the explosion is unique to different chemicals.
But I'm getting ahead of myself. First lets start off with what a firework shell is composed of and how it packed together. First you need a shell/container that holds all the fun inside safely. Inside the shell you need black powder/gun powder, a bursting charge (the actual firecracker that booms in the sky) and stars. The stars are where the aerial display comes to life. In this shell is a colorful chemistry lesson. As I said before different elements/compounds have different chemical properties (any old chemistry students remember the old standard flame test?) That was always a fun lab day huh? :) Anyway, if you have an excellent memory you might could recall that lithium produces a red flame, barium a green flame and copper a blue flame. Now there are MANY others naturally, but this is just to give you the idea of where colors come from in a fireworks display. Now this is just for luminescent fireworks.
Have you ever noticed fireworks that change colors or seem to "fizz" on their own? Those are incandescent fireworks...made up of different things but a main ingredient is charcoal of all things. Have you ever noticed how charcoal goes from black to red to orange to white...this also reflects how hot it is with white meaning it's reached is prime temperature? Same with fireworks. A lot of the incandescent fireworks will appear gold and "sparkly" or as I refer to them as "disney fireworks" because they remind me of Cinderella's castle.
Now that you know about colors, what about shapes? Have you noticed hearts, smiley faces and stars (especially for the 4th)? How do they do that??? Well this has to do with how the stars from inside the shell are arranged. The more tightly woven together they are packed, the more compact the display of color, the more widely spaced, the more room is taken over in the night sky. Also, if the stars are arranged in a pattern...such as a star...you see a star in the sky.
So here's hoping you enjoy your night of excited electrons dancing in the sky. My family will finally be able to spend America's birthday together watching the show downtown tonight. Can't wait. Have fun, be safe!