The Chemistry behind Fireworks Finally, it’s New Year’s Eve; the highlight of your Christmas holiday. While you’re enjoying a glass of champagne and a couple of “oliebollen” (Dutch doughnuts) with friends and family, the countdown begins. 3, 2, 1, BANG! The sounds and flashes of fireworks accompany the beginning of the New Year. But did you know all those magnificent colours and loud sounds are chemistry? By: Nikita de Keijzer & Valery Tjoeng
We would like to start the first Origin of the year with a big bang. As 2011 is the international year of chemistry, what better spectacular topic to write about than fireworks? Dive into the colourful history of firecrackers and learn about the science behind the flashes and bangs.
2200 year history The fireworks we know today have developed over 2200 years. The use of fireworks has also changed throughout the centuries. An overview of the most important developments in the history of fireworks is displayed in the timeline.
alchemist Ge Hong described the ingredients of black powder: charcoal, sulphur and saltpetre or potassium nitrate. He observed that when this black mixture was heated in a fire, it produced a bright flame. It would even explode when it was stuffed in a bamboo shoot. It is interesting to note that the ingredients of black powder were commonly used for culinary purposes and to treat various ailments. Hence the Chinese word for gunpowder is huǒyào ( ), meaning fire medicine. Today, the alchemist and doctor Sun Simiao is regarded by the Chinese as the father of gunpowder.
2 nd Generation fire crackers The first fire cracker About 2200 years ago, Chinese people discovered the ancient precursor of the fire cracker we know today: exploding bamboo shoots. When thrown in a hot fire, the air and juices in the green bamboo shoots heat up and expand until the pressure built up inside causes the bamboo to crack with a loud bang. The sound scared away people and animals, and the Chinese people believed they could use the exploding bamboo shoots to scare away the evil spirit Nian. Since the 5th century, firecrackers were also used to pray for happiness and prosperity by the Chinese people. Although firecrackers are not made of bamboo shoots anymore, the Chinese characters for firecrackers, (bàozhú), literally mean exploding bamboo.
Black powder It was not until the invention of black powder, also known as gunpowder, that the next generation of fire crackers were created. By 300 A.D. the Chinese
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Origin - Universiteit Leiden
During the 9 th century, Chinese emperors of the T’ang dynasty used gunpowder to put on great firework displays for their personal entertainment. According to legend, the Chinese monk Li Tian of the city Liu Yang in Hunan Province, China, ignited a series of bamboo tubes with black powder to get rid of evil spirits. Today, Liu Yang remains the region which produces fireworks and the monk Li Tian is still honoured every year on April 18th for his invention of fire crackers.
Fireworks taking over the rest of the world Although the Chinese tried to keep the invention of black powder secret, the Arabs learned about it in the 13th century. It is said that Marco Polo brought fireworks to Italy around the same time. The Italians advanced the development of firecrackers and into aerial shells. Around the 1830s, they were also the first to add metallic salts and chlorinated powders to create other colours (see Table 1) than the orange, gold and silver that were the only possibilities until then.