Chemistry as a science is a important part of many things and events that we witness in our lives. During winter, one of the many uses of knowledge of chemistry becomes more and more visible, as the New Year’s Eve becomes closer and closer, and finally on that day we become witnesses of one of the most beautiful shows that chemistry can offer us.
Well, saying that chemistry is most responsible science behind fireworks isn’t quite true, because the primary science or engineering branch that deals with fireworks is called pyrotechnics. However, a large part of this science, if not the largest, is chemistry. All these compositions that are used in fireworks, are actually mixtures of chemical reagents that wait to be initiated into a complex mix of chemical reactions that we percieve as fireworks.
One of the main and most basic of these composition is black powder. Black powder is regarded as being invented in China, where the Chinese used it to make bombs that they used against Mongols. Later, it was introduced in the Islamic world and in Europe (in the 13. century), and has since than been used extensively as an explosive and gunpowder.
Black powder is composed of a nitrate salt (usually potassium nitrate, also known as saltpeter), sulfur and charcoal. The exact percentages have had different values throughout history, and even today, the amounts can vary depending on the use of black powder. The most common and most simple chemical equation which describes the reaction that occurs when black powder ignites, states that the products of the reaction are nitrogen gas, carbon dioxide and various potassium salts (potassium sulfide, potassium carbonate or potassium sulfate; or mixtures of the mentioned salts in various ratios).
In a pyrotechnic sense, the gases N2 and CO2 contribute to many of the uses of black powder, such as propelling “stars” or other types of pyrotechnic objects that produce various effects. The expansion of gases that are produced in the mentioned reaction are also often used to make loud explosions by closing small amount of black powder in a compressed space, and igniting it. There is also one more use of black powder – to produce white (or sometimes gray) smoke that is the result of small particles of the before mentioned potassium salts that get dispersed in the air after ignition of black powder.
Regardless of the way or method in whic black powder is used, it was and remains one of the most important compositions in the science of pyrotechnics. If one is interested in learning more about mechanisms behind pyrotechnic reactions, it’s not a bad idea to start from chemistry basics.
Tags: black, chemistry, gunpowder, history, powder, pyro, pyrotechnics, science —
