The Chemistry of Explosives: Jacob Braunfeld

The first instances of black powder throughout history date back to 1200 AD in ancient china. They used black powder for fireworks, and in the following centuries, gunpowder started to be utilized for much more than just pyrotechnics. Black powder started to be used by countries in their weaponry during war. Guns and cannons that used black powder became the weapons of choice for all fighting, and they were extremely effective, and deadly. Gunpowder is a mixture of 3 different substances, which in the right ratio can prove to be very explosive.

The powder is comprised of Potassium Nitrate, Charcoal, and Sulfur. Potassium Nitrate (KNO3), serves as a source of a vital part of combustion, oxygen. At high temperatures, Potassium Nitrate decomposes and releases oxygen, this is useful because it helps fuel the flame, and also makes it so the mixture can sustain itself. This means that even if it is smothered, it will still burn due to the continuous presence of oxygen. The charcoal serves as a fuel to continue the burn. In addition to oxygen, the other component necessary for combustion is a fuel of some sort. Charcoal provides this because in addition to it being made of carbon, it is also made up of broken down cellulose (living wood) and those serve to fuel the flames. The purpose of sulfur in black powder, is to start out the reaction. charcoal takes a relatively high temperature to ignite, so it would be difficult to do if there was no sulfur. Sulfur ignites at a much lower temperature, so once that is ignited, the powder becomes a temperature high enough to ignite the charcoal and cause an explosion.

Technically, gunpowder itself does not cause an explosion. The definition of an explosion is a violent and destructive shattering or blowing apart of something. When black powder is contained in something, then pressure does build up, and will explode through the path of least resistance, but in the open air gunpowder has a different result. Just igniting gunpowder leads to a fast burn. Which in essence is what an explosion is. But even though you may get a nice pyrotechnic show you wont make a crater in the ground by lighting off plain black powder.

Black powder was very useful when it was used, but more recent technological advancements in explosives have created smokeless powder which we use today. Smokeless powder or just any propellant is not considered an explosive. it is formulated  to create gas that propels the bullet down the chamber, rather than an explosion which pushes the bullet forward. It is much more powerful than black powder, and it provides a tactical advantage of not giving away the position of troops by making a lot of smoke.