potassium nitrate(redirected from Chilean saltpetre)
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potassium nitrate,chemical compound, KNO3, occurring as colorless, prismatic crystals or as a white powder; it is found pure in nature as the mineral saltpeter, or niter. (The name saltpeter is also applied to sodium nitratesodium nitrate,
chemical compound, NaNO3, a colorless, odorless crystalline compound that closely resembles potassium nitrate (saltpeter or niter) in appearance and chemical properties. It is soluble in water, alcohol, and liquid ammonia.
..... Click the link for more information. , although less frequently.) It is slightly soluble in cold water and very soluble in hot water. Potassium nitrate is prepared commercially by the reaction of potassium chloride with sodium nitrate. When potassium nitrate decomposes (on heating) it releases oxygen; it has been used extensively as the oxygen-supplying component of gunpowder since about the 12th cent. It is also used in explosives, fireworks, model rocket propellants, matches, and fertilizers, as a preservative in foods (especially meats), and in the manufacture of nitric acid and of glass.
a salt; colorless crystals. Density, 2.11 g/cm3; melting point, 339°C. Readily soluble in water (31 g in 100 g H2O at 20°C; 246 g at 100°C).
Mixtures of potassium nitrate and organic substances are easily flammable and burn vigorously. Potassium nitrate is prepared by reacting HNO3 or nitrous gases with K2C03 or KC1. Potassium nitrate is used as a fertilizer, in glassmaking, and in the production of gunpowder.
In agriculture, potassium nitrate containing 44 percent K2O and 13 percent nitrogen is used as a base fertilizer (applied in the spring) and as a top-dressing for chlorine-sensitive crops (flax, potatoes, tobacco, grapes).