Sodium borate hydrate

Disodium Octaborate Tetrahydrate. The composition of a commercially available sodium borate hydrate, 66.3 wt % B203, POLYBOR (64), corresponds quite closely to that of a hypothetical compound, disodium octaborate tetrahydrate, Na2Bg013 TH O or Na O 4-B203 4H20. This product dissolves rapidly in water without the temperature decrease, which occurs when the crystalline borates dissolve, and easily forms viscous supersaturated solutions at elevated temperatures. The solution pH decreases as the concentration increases (Table 10). The solubility of the product is shown compared with that of borax (33) ... 

Borax is usually mined from salt lakes as sodium borate hydrate. 

Sodium borate (borax) [1330-43-4] M 201.2, m 741 , d 2.37. Most of the water of hydration was removed from the decahydrate by evacuation at 25° for three days, followed by heating to 100° and evacuation with a high-speed diffusion pump. The dried sample was then heated gradually to fusion (above 966°), allowed to cool gradually to 200°, then tranferred to a desiccator containing P2O5 [Grenier and Westrum J Am Chem Soc 78 6226 1956]. 

Sodium borate (decahydrate, hydrated borax) [1303-96-4] M 381.2, m 75 (loses 5H2O at 60 ), d 1.73. Crystd from water (3.3mL/g) keeping below 55° to avoid formation of the pentahydrate. Filtered at the pump, washed with water and equilibrated for several days in a desiccator containing an aqueous solution saturated with respect to sucrose and NaCl. Borax can be prepared more quickly (but its water content is somewhat variable) by washing the recrystd material at the pump with water, followed by 95% EtOH, then Et20, and air dried at room temperature for 12-18h on a clock glass. 

Alum Borax Natron Iron vitriol Mineral Mineral Mineral Mineral or synthetic Sulfate of aluminum and other metals (e.g., potassium alum) Hydrated sodium borate Natural mixture sodium carbonate and sodium bicarbonate Hydrated iron sulfate... 

BORAX. This hydrated sodium borate mineral, NaiBtOy 101 1, O, is a product of evaporation from shallow lakes and plays. Borax crystallizes in the monoclinic system, usually in short prismatic crystals. Its color grades from colorless through gray, blue to greenish. Vitreous to resinous luster of translucent to opaque character. Hardness of 2-2.5, and specific gravity of 1.715. 

XBorax, sodium borate) 6)Sax( 1957),374 7)USSpec SS-S-535A(1958) (Sodium borate, deca-hydrate, tech borax) 8)R.F.Gould,Edit "Borax to Boranes ,Advances in Chemistry Series No 32 American Chemical Society,Washington,DC(1961), 240pp... 

Stock solutions (1000 mg/L in acetonitrile) of 2,4,6-trinitrotoluene (TNT), 1,3,5-trinitrobenzene (TNB), 2,4-dinitrotoluene (2,4-DNT), and 4-amino-2,6-dinitrotoluene (4-Am-2,6-DNT) (Supelco). Sodium dodecyl sulfate (SDS) and sodium borate 10-hydrate. Standard solutions of the various explosives should be prepared daily (using the proper safety precautions) in an SDS-containing electrophoresis buffer. Platinum and silver wires, 0.1mm diameter. 

Crude and refined hydrated sodium borates and hydrous boric acid are produced from kernite and tincal. The ore is fed to the dissolving plant and mixed with hot recycle liquor. Liquor and fine insolubles are fed to a primary thickener. The strong liquors are crystallized in a continuous vacuum crystallizer. 

Borax pentahydrate (also known as Neobor ) is the most common form of sodium borate used in a variety of industries. Its advantages when compared with borax lie in the lower transportation, handling, and the storage cost of a more concentrated product. Borax pentahydrate readily effloresces upon heating. It starts to dehydrate at about 65°C, loses all water of hydration when heated above 320°C, and fuses when heated above 740°C. In water, it hydrolyzes to give a mildly alkaline solution with excellent buffering properties.7... 

Ba0-B203-H20, is used as a corrosion inhibitor in industrial paints and primers, a biocide in paints and plastics, and to a lesser extent as a fire retardant additive. It is generally manufactmed by reacting barium sulfate with a sodium tetraborate hydrate in water. Several other crystalhne hydrated barium borates are also known but have less industrial importance. 

Acidity/alkalinity pH = 5.3 (1% w/v aqueous solution) Solubility ceratonia is dispersible in hot water, forming a sol having a pH 5.4—7.0 that may be converted to a gel by the addition of small amounts of sodium borate. In cold water, ceratonia hydrates very slowly and incompletely. Ceratonia is practically insoluble in ethanol. 

Pure sodium tetraborates are produced from crushed raw sodium borate minerals (tincal, kernite) by dissolution with heating in a weak borax-containing mother liquor, separating off the impurities (clays) and selective crystallization. Either the penta- or deca-hydrate is formed during vacuum crystallization, depending upon the temperature (above or below 60.8°C). 

Sodium borate (decahydrate, hydrated borax) [1303-96-4] M 381.2, m 75 (loses 5H2O at... 

ZIRCAT (7440-67-7) Finely divided material is spontaneously flammable in air may ignite and continue to bum under water. Violent reactions with oxidizers, alkali hydroxides, alkali metals (and their compounds), carbon tetrachloride, cupric oxide, lead, lead oxide, lead peroxide (combined material can burn explosively, and is sensitive to friction and static electricity), nitryl fluoride, oxygen difluoride, phosphoms, potassium, potassium compounds (potassium chlorate, potassium nitrate), sodium borate, sodium hydroxide. Explodes if mixed with hydrated borax when heated. Contact with lithium chromate may cause explosion above 752°F/450°C. Forms explosive mixture with potassium chlorate. Dusts of zirconium ignite and explode in a carbon dioxide atmosphere. Contact with ammonium-V-nitrosophenylhydroxylamine above 104°F/40°C forms an explosive material. Incompatible with boron, carbon, nitrogen, halogens, lead, platinum, potassium nitrate. In case of fire, use approved Class D extinguishers or smothering quantities of dry sand, crushed limestone, clay. 

Borax (Hydrated Sodium Borate). Amethyst Galleries, Inc. http //mineral.galleries.com/minerals/carbonat/borax/ borax.htm (accessed on November 12, 2005). 

With increasing concentration of boric acid (> 0.025 M) the hydration-dissociation — equilibrium is shifted towards free B(OH)3 molecules, which associate progressively. These macromolecules can be regarded as polyborate anions (J4). Some polynuclear species, B303(0H)4, B303(0H)5" and the very stable tetraborate ion, which is the most predominant dinegative ion in sodium borate solutions, have been detected (Fig. 3). 

Borax is commonly used as a pesticide and fungicide. It s made of sodium borate (NaB02), but it s most often found as the hydrated compound, Na2B407 IOH2O. It can also be used as a cleaning agent, or to soften hard water. 

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