Gunpowder, also known as black powder to distinguish it from modern smokeless powder, is the earliest known chemical explosive. It consists of a mixture of sulfur (S), charcoal (C), and potassium nitrate (saltpeter, KNO3). The sulfur and charcoal act as fuels while the saltpeter is an oxidizer.

Because of its incendiary properties and the amount of heat and gas volume that it generates, gunpowder has been widely used as a propellant in firearms, artillery, rockets, and fireworks, and as a blasting powder in quarrying, mining, and road building.

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