Gunpowder is also known as black powder. It holds an important place in the history of chemistry. It is primarily used as a propellent, but it can also explode. Gunpowder was invented in China during the 9th century. The Chinese alchemists made gunpowder by mixing three elements together. They were sulfur, charcoal, and saltpeter. Saltpeter is another name for potassium nitrate. The most common source of the charcoal was the willow tree, but hazel, laurel, grapevine, elder and pine cones have also been used. Sugar can be used in place of charcoal as a fuel when making gunpowder.
Emperor Wu-Di who ruled from 156-87 B.C., was the ruler who provided financing for the research that led to the invention of gunpowder. Ironically, their research was intended to find a way to provide eternal life. Instead, they invented a product that would eventually be used as a dangerous weapon and would be responsible for the deaths of many people.
When the ingredients of the gunpowder were ground together, the result was a powder that was known as serpentine. Making gunpowder was a dangerous activity, since the ingredients needed to be remixed before using. Sometimes, people who were making gunpowder, would add wine, water or another liquid to reduce the hazard of sparks causing a fire. After bing mixed with liquids, the powder could be pushed through a screen to make small pellets, that were then allowed to dry.
Black powder consists of a fuel (charcoal or sugar) and an oxidizer (saltpete or niter), and sulfur, to allow for a stable reaction. The charcoal plus oxygen forms carbon dioxide and energy. Without the oxidizing agent the reaction would be slow. The carbon in a fire needs to draw oxygen from the air. The saltpeter or niter, gives the gunpowder extra oxygen. Nitrogen, carbon dioxide gases and potassium sulfide are formed when potassium nitrate, carbon and sulfar are joined. To provide the needed propelling action, nitrogen and carbon dioxide form the expanding gases needed.
The mixture was used as a powder to treat skin diseases and to kill insects, before its use as a weapon was explored. The Chinese alchemists began to experiment with filling tubes with the gunpowder. They later began attaching bamboo tubes to arrows and launching them with bows. They quickly learned that the gunpowder tubes could launch themselves with the power the excaping gases produced. This was the first rocket.
While there have been many changes and improvements over the years, all gunpowder got it’s beginnings from this original “Black Powder”.
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