During Tet and various festivals, fireworks are almost indispensable. However, few people know the formula for creating them. Additionally, it’s not always possible to achieve the desired shapes when fireworks explode.
The primary component is black powder (gunpowder), which is essential for making all types of fireworks. Gunpowder is a mixture of charcoal, sulfur, and potassium nitrate. When exposed to a spark, these three components combine to create a very powerful explosive. Specifically, sulfur and charcoal consume all the oxygen from potassium nitrate, which serves as a large supply. As with any combustion, the temperature will rise, especially within the confined space of a firework shell. The more confined the space, the higher the temperature rises.
This combustion activates the “additives” of the shell, in other words, the substances that produce the desired colors and effects. Fueled by heat, the electrons of these additives emit bursts of light. What color light? For centuries, firework makers only produced bright yellow and white flashes. Later, they learned to enrich the color palette with red and green (the two easiest colors to create), as well as blue, purple, pink, and orange.
(Image: elsewhere)
Of course, the exact formula for these additives is a closely guarded secret. It is the key to competitive advantage. However, the most commonly used metal salts are based on barium, copper, sodium, and strontium. Copper chloride produces a beautiful blue color, while strontium chloride gives off a brilliant red. By skillfully combining these two substances, one can achieve a wonderful purple hue.
Modern fireworks are virtually limitless. However, chemists cannot meet every demand. If you ask them for a very bright blue color, they might frown. To enhance brightness, the temperature must be increased further. However, at over 1,200 degrees Celsius, copper chloride decomposes and no longer emits blue light.
If you were to ask if it is possible to create fireworks that form specific shapes or letters when they explode, they would likely respond: Well! That’s quite difficult.
(Image: Jennings Osborne Family)
