How Fireworks Work!
Nomad authors are a dedicated bunch! All the activities in Nomad Press books are vetted by the authors (and often their children, classrooms, and neighborhood kids). Sometimes that makes for comical outcomes, like the experiment described in the following guest blog post from Nomad author Susan Berk Koch! Luckily, Sue’s porch is just fine. Have a blast reading, and be safe tomorrow during July 4 celebrations!
And kids, if you do any science experiments with heat, always have an adult help you!
So how do fireworks work, exactly? Fireworks are just chemical reactions!
A firework requires three key components: an oxidizer, a fuel, and a chemical mixture to produce the color. The oxidizer breaks the chemical bonds in the fuel, releasing all the potential energy that’s stored in those bonds. To ignite this chemical reaction, all you need is a bit of fire in the form of a fuse or a direct flame.
Each firework is made of tube that contains gun power and dozens of pods. Inside the pods are packs of chemicals. It’s the metal salts and metal oxides that create the color! Each pod inside one of the tubes creates a dot of color in the fireworks explosion. Imagine how many pods there must be!
How did people come up with fireworks in the first place?
According to the American Pyrotechnics Safety and Education Foundation, around 800 BCE, Chinese alchemists mixed together saltpeter, sulfur, and charcoal and created gunpowder. They were actually looking for a recipe for eternal life, but they still changed the world with their invention! They used it to scare away evil spirits – they were more focused on the noise factor.
The Smithsonian website states that Europeans were introduced to gunpowder during the Crusades in the thirteenth century, not by Marco Polo (although he usually gets credited with this). I thought so, too. Good thing I looked this up before our next Trivia Night!
It seems obvious that heat sets off the fireworks. Heat is also what starts the chemical reaction of the substances inside the tubes.
Heat excites the electrons of the metal salts and metal oxides and causes them to jump to a higher energy level. When the electrons go back to their original state, they release excess energy as wavelengths of light.
The different elements in the chemical compounds release different amounts of energy. To us, that means different colors!
For red, add lithium. (Li)
For yellow, add sodium (Na) compounds.
For blue, add copper chloride compounds.
For green, you add barium. (not listed above)
For purple, add a mixture of blue-producing copper and red-producing strontium. (Sr)
For orange, add calcium salts. (CaCl2)
For white and silver, add aluminium, magnesium, or titanium.
This type of light is called luminescence.
Luminescence is light that is given off when electrons in elements move around. This happens at lower temperatures than incandescence, hence the term “cold light.” This can happen via a chemical reaction, stress on crystal structures, an electric current passing through certain substance, or when energy such as UV light passes through a substance.
Incandescence is light produced when objects are hot enough to glow. So it is also called “hot light.” Examples include a lit candle or match.
Check it out! I colored in a periodic table with the elements that have electrons which excite and jump levels, producing colors.
I attempted a fun experiment in honor of the Fourth of July. I tried to make a black snake! When baking soda and powdered sugar react with heat, they create carbon dioxide and a cool black snake. It smells like burned marshmallows!
I used kerosine and it gets, uh, hot! I decided against posting the ingredients after I ended up with a huge scorch mark on our deck. You can purchase a safer version. Here’s what is should look like when it’s under control.
Here’s to clear skies! Enjoy the fireworks!