We’ve got your answer: Magic.
Okay, so it only feels like magic. But for many it remains a mystery, which is why we’ve broken down all the details about how fireworks work, what they’re made of, why they do what they do, and so much more.
How are Fireworks Made?
Fireworks are made with a variety of components and materials, depending on their type:
When most people think of traditional fireworks—ones that fire into the sky and burst in big, colorful displays—they’re thinking of aerial fireworks. Aerials come in different kinds, but at their core they’re made up of:
- Tail (or Stick): The long plastic or wooden stick at the bottom of the firework that lets you position and accurately aim the firework.
- Fuse: What you light to ignite the firework. Most consumer fireworks have visco fuses, which are made of a string-wrapped black powder (a.k.a. gunpowder) core and a wax or lacquer-coated exterior. This exterior makes them water resistant, and produces a visible flame so you can safely gauge when the firework will ignite.
- Mortar (or Charge): What shoots the firework into the sky. Mortars are usually made of tightly packed black powder to give the needed power to get those fireworks so high.
- Shell: What it’s all about. The shell is what's launched into the air and what explodes to give those incredible displays. Shells are generally made up of a paper and string cylinder, stars (cubes, cylinders, or spheres of sparkler-like material that create the smaller, colorful effects), and a firecracker-like bursting charge at its center.
Unlike aerial fireworks, fountains don’t shoot up into the sky—instead, these ground effect fireworks dazzle in place, shooting off a cascade of colorful sparks where they’re lit. Generally fountains are made up of a core of fuels and metal compounds, and are contained in a plastic or paper tube with clay plugs at either end. They also have a fuse similar to aerials.
Spinner and Wheel Fireworks
Similar to fountains, spinners and wheels don’t shoot up into the sky. However, they’re generally fixed to a mount or pole, which allows them to spin once ignited. Most spinners and wheels have a plastic disk at their center, with gerbs (very similar to fountains) attached around the edge.
Unlike fireworks, these novelty favorites are held by a wire stick while ignited. The tip of the stick is coated with a balance of fuel, binder, and oxidizer, which allows the sparkler to burn slowly instead of exploding like a firework.
What are Fireworks Made Of?
Okay, so we know what parts our favorite fireworks are made of. So what actually makes those incredible colors and effects? And what actually creates all that power?
- Black Powder: Back to classic gunpowder. This ancient compound is a mixture of charcoal, potassium nitrate, and sulfur. When lit, the heat sets off a chemical reaction—as the potassium nitrate burns it gives off oxygen, helping the charcoal and sulfur burn and producing hot gases that propel the firework into the sky.
- Dextrin: This is a common binder used for sparklers and shell stars. It’s made of a combination of ethanol glycol, hydroxide, oxygen, and nitrogen.
- Metal Salts: These bad boys are packed into the stars in the shell of fireworks, and they’re what create such spectacular colors. To get each color, you need:
- Red: Lithium or strontium carbonate
- Orange: Calcium chloride
- Yellow: Sodium nitrate
- Green: Barium chloride
- Blue: Copper chloride
- Purple: Lithium or strontium carbonate and copper chloride
- White: Barium oxide
- Gold: Iron, charcoal, or lampblack
- Silver: Aluminum, magnesium, or titanium
How do Fireworks Work?
Materials? Check. Chemistry and compounds? Check. Now it’s time to figure out how it all comes together. Let’s take it back to Chemistry 101:
- Charles Law: According to this basic law of physics, as the temperature of enclosed gas increases, the volume increases (as long as the pressure stays constant.) When a firework explodes, hot gases are quickly produced and expand rapidly, creating that incredible boom—which is actually a sonic boom! This happens when the gases expand at a faster rate than the speed of sound. Awesome.
- The Law of Conservation of Energy: When the firework explodes, what actually happens? In layman’s terms, the energy of the firework is converted into other forms of energy: heat, light, movement, and sound. Basically, the total energy inside of the firework before it ignites must equal the remaining energy after it explodes (as well as the energy released as the four other forms).
- The Law of Conservation of Movement: Ever wondered why firework displays (like those shimmering rains and gorgeous willows) are perfectly symmetrical? This basic law of physics means that the momentum of the fireworks must be the same before and after an explosion, meaning that the effect explosions must be symmetrical and equally shaped.
- Luminescence: Generally, the light from a firework is caused by luminescence. When it explodes, the black powder inside it creates heat, causing the metal salts to absorb energy and emit light.
- Newton’s Third Law of Motion: For every action, there must be an equal and opposite reaction—think: a rocket. As the black powder inside of the firework burns, it gives off hot gases that fire backward. The force of those gases is like the blast force of the rocket, creating an equal and opposite reaction that shoots the firework up into the sky.
And there you have it! With so much chemistry, so many materials, and so much attention to detail, it’s no wonder that fireworks are such incredible, eye-catching extravaganzas.
Ready to light up the night with an extravaganza of your own? Shop your favorite fireworks now with Red Apple, and get ready to impress your friends with your in-depth chemistry knowledge!