Potassium nitrate
Description
Clear colorless crystals that are slightly hygroscopic. Potassium nitrate has been used since the 1300s as an ingredient in gunpowder. It was used in gold smelting, glass making, and textile dyeing. In a closed environment, a salt solutions saturated salt solution of potassium nitrate will form an equilibrium at a relative humidity of about 93% (20C).
Synonyms and Related Terms
niter; nitre; saltpeter; Bengal saltpeter ; sal prunella; kaliumnitrat (Dan., Deut.); salptre (Fr.); nitrato di potassio (It.); kaliumnitraat (Ned.); azotan potasu (Pol.); saletra potasowa (Pol.);
Other Properties
Soluble in water, glycerol. Slightly soluble in ethanol.
Deliquescent point at 20C is 93.2 % RH (see salt solutions saturated salt solutions)
| Composition | KNO3 |
|---|---|
| CAS | 7757-79-1 |
| Melting Point | 333 |
| Density | 2.1062 |
| Molecular Weight | mol. wt. = 101.1 |
| Boiling Point | 400 (dec) |
Hazards and Safety
Dangerous fire and explosion risk when shocked, heated or in contact with organic materials. Strong oxidizing agent.
International Chemical Safety Card
Authority
- G.S.Brady, G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p. 632
- Hermann Kuhn, Hermann Kuhn, Conservation and Restoration of Works of Art and Antiquities, Butterworths, London, 1986
- Susan E. Schur, Susan E. Schur, Conservation Terminology: A review of Past & Current Nomenclature of Materials, Technology and Conservation, Spring (p.34-39); Summer (p.35-38); Fall (p.25-36), 1985
- Michael McCann, Michael McCann, Artist Beware, Watson-Guptill Publications, New York City, 1979
- Wikipedia, the free encyclopedia, at http://www.wikipedia.com Comment: http://en.wikipedia.org/wiki/Potassium_nitrate (Accessed Nov. 9, 2005)