The chemistry of fireworks
The colours in fireworks are produced by pyrotechnic stars which produce coloured light when ignited.
These stars contain five basic elements.
- Metal Salts – To Produce Colour
- Fuel – To allow the star to burn
- Oxidising Chemical – To provide oxygen for the combustion of the fuel
- Chlorine Donating Compound – To help strengthen the colours
- Binding Chemical – To help hold the mixture together
| NAME | SYMBOL | FIREWORKS USAGE |
|---|---|---|
| Aluminium | Al | Aluminium is used to produce silver and white flames and sparks. It is a common component of sparklers. |
| Barium | Ba | Barium is used to create green colours in fireworks, and it can also help stabilize other volatile elements. |
| Carbon | C | Carbon is one of the main components of black powder, which is used as a propellent in fireworks. Carbon provides the fuel for a firework. Common forms include carbon black, sugar, or starch. |
| Calcium | Ca | Calcium is used to deepen firework colours. Calcium salts produce orange fireworks. |
| Chlorine | Cl | Chlorine is an important component of many oxidizers in fireworks. Several of the metal salts that produce colours contain chlorine. |
| Copper | Cu | Copper compounds produce blue colours in fireworks. |
| Iron | Fe | Iron is used to produce sparks. The heat of the metal determines the colour of the sparks. |
| Potassium | K | Potassium helps to oxidize firework mixtures. Potassium nitrate, potassium chlorate, and potassium perchlorate are all important oxidizers. |
| Lithium | Li | Lithium is a metal that is used to impart a red colour to fireworks. Lithium carbonate, in particular, is a common colourant. |
| Magnesium | Mg | Magnesium burns a very bright white, so it is used to add white sparks or improve the overall brilliance of a firework. |
| Sodium | Na | Sodium imparts a gold or yellow colour to fireworks, however, the colour is often so bright that it frequently masks other, less intense colours. |
| Oxygen | O | Fireworks include oxidizers, which are substances that produce oxygen in order for burning to occur. The oxidizers are usually nitrates, chlorates, or perchlorates. Sometimes the same substance is used to provide oxygen and colour. |
| Phosphorus | P | Phosphorus burns spontaneously in air and is also responsible for some glow in the dark effects. It may be a component of a firework’s fuel. |
| Sulphur | S | Sulphur is a component of black powder, and as such, it is found in a firework’s propellant/fuel. |
| Antimony | Sb | Antimony is used to create firework glitter effects. |
| Strontium | Sr | Strontium salts impart a red colour to fireworks. Strontium compounds are also important for stabilizing fireworks mixtures. |
| Titanium | Ti | Titanium metal can be burned as powder or flakes to produce silver sparks. |
| Zinc | Zn | Zinc is a bluish white metal that is used to create smoke effects for fireworks and other pyrotechnic devices. |
