Exploring the science behind fireworks, discover how different elements are used to produce different colors of fireworks.
- In the mid-19th century, the inventor of the Bunsen burner, Robert Bunsen, discovered that pure elements burn with distinctive flame colors.
- Potassium produced a lilac flame.
- Copper burned green.
- The different color flames produced were due to the movement of electrons between electron shells.
Fireworks. Dazzling and explosive.
Their brilliant blues and greens, reds and oranges, can transform the night sky.
But just how are the different colors made?
Back in the mid 19th century, the inventor of the Bunsen burner, Robert Bunsen, discovered the phenomenon of flame colors.
He found that different pure elements burned in a Bunsen flame with distinctive colors.
Potassium produced a lilac color.
Copper burned green.
Calcium glowed an orangey red.
And sodium a bright yellow.
Every element has a unique color signature, with metal elements producing the most distinctive flames.
Potassium - Lilac. Copper - Green. Calcium - Orangey Red. Sodium - Bright Yellow.
We now know this is because of the structure of their atoms, with their different arrangements of electrons.
Electrons always position around the positive nucleus in distinct shells, with electrons in the same shell having the same energy.
The inner shells have the least energy...
And further from the nucleus, the shell's energy level increases.
When heat energy is supplied to an element, electrons become excited and can "jump up" to a higher energy level.
And as they relax and "drop back," they give out energy as light.
The color emitted depends on the electron arrangement and the gap between lower and upper energy levels in a particular atom, which is why different elements give off their own unique color.
At the time, Bunsen used the characteristic colors to identify different elements.
And today, that knowledge is still applied to the pyrotechnics of colored fireworks.
A good blue display is produced from copper chloride.
Yellow fireworks contain sodium salts...
And bright red explosions contain metals like strontium and lithium.
So an understanding of flame colors is behind the most breathtaking of firework displays...
All created by electrons jumping between energy levels.