Gunpowder,also known since the late 19th century as black powder,was the first chemical explosive and the only one known until the mid-1800s. It is a mixture of sulfur,charcoal,and potassium nitrate (saltpeter)—with the sulfur and charcoal acting as fuels,while the saltpetre works as an oxidizer.Because of its burning properties and the amount of heat and gas volume that it generates,gunpowder has been widely used as a propellant in firearms and as apyrotechnic composition in fireworks.
杏仁茶甜甜
