The Science of Fireworks


By Christa Cuccia

What are The Fourth of July, baseball games and New Years Eve all known for? FIREWORKS of course! The bright and sparkling lights from fireworks are so unique and beautiful and a great firework show can be unforgettable. But what are fireworks? How do they create those magical displays in the sky? Fireworks may seem astonishing, but the science behind them is easy to understand.

Back to Basics

Let’s start with the basics. Understanding pyrotechnic devices such as sparklers and firecrackers are a great foundation. The sparkler creates the bright light and the firecracker demonstrates the explosion. Both of these qualities are found in most fireworks.

Firecrackers have been around for a long time, dating back hundreds of years. A firework contains either Black Powder (gunpowder) or Flash Powder. These powders are put in a tight tube with a fuse to light the powder. Black powder contains things like charcoal, sulfur and potassium nitrate. If a firecracker needs to have a brighter explosion then it may contain aluminum instead of or in addition to the charcoal.

Sparklers on the other hand, are surprisingly much different from firecrackers. A sparkler burns for a long period of time and produces bright lights. Sparklers can also be called “snowball sparklers” because of the ball of sparks that form around the tip of the stick. A sparkler is made of several different components that include a binder, fuel, an oxidizer and iron or steel powder. Charcoal and sulfur make up the fuel and the binder is usually sugar or a starch. These chemicals are then mixed with water to form slurry that can be coated with wire or poured in a tube. Voila! You have a sparkler.

Adding Metal for an Extra Shine

Aluminum, iron, steel, zinc and magnesium dust are all commonly added to fireworks in order to create brighter and more brilliant sparks. Metal flakes heat up until they are incandescent and shine brightly. Extra chemicals are added to create the vibrant and unique fun colors.

Extension Questions

  • What other chemicals do you think are added to fireworks?
  • What are some of the different sounds produced by fireworks? How are they produced?
  • Did you know science played such a big role in the production of fireworks?