melting point of anhydrous sodium sulfate
The melting point of anhydrous sodium sulfate is 884 degrees Celsius. It is soluble in water, glycerol and hydrogen iodide and is insoluble in alcohols.
Common laboratory reagent used in kjeldahl nitrogen determination; drying agent; solvent for extraction of organic compounds.
Sodium sulfate is an important chemical raw material in the manufacture of glass and ultramarine blue, Kraft paper, paperboard, ceramic glaze and dyeing textiles. It is also an ingredient in a wide variety of synthetic detergents and filler in soaps.
It is widely used in a large number of other applications, including frosting windows, carpet fresheners and as an additive to cattle feed. It is considered a non-toxic compound, but care should be taken when handling it, especially in dust.
The hygroscopic nature of anhydrous sodium sulfate allows it to absorb moisture from the air; therefore, it is an excellent drying agent. Sodium sulfate is most commonly obtained as Glauber’s salt (Na2SO4), the decahydrate.
When the hydrated form of the sodium sulfate is exposed to heat, it emits toxic fumes of sulfur oxides and sodium oxide. It is a major by-product of sodium dichromate production and a wide range of chemical processes where leftover sulfuric acid is neutralized with sodium hydroxide.
Sodium sulfate is not biodegradable and its natural occurrence in the environment has long been a concern. It participates in the sulfur cycle, reducing to sulfides by anaerobic bacteria and re-oxidizing in the atmosphere and oceans to sulfide and sulfate. It is a major component of seawater and many saline or alkaline lakes.