Phosphoric acid is a clear, colourless, odourless, viscous, syrupy liquid (75-85% aqueous solution). It will not burn but it can decompose at high temperatures forming toxic phosphorus oxides. Certain chemical reactions can liberate hazardous gases. Contact with metals liberates flammable hydrogen gas. Phosphoric acid is CORROSIVE to the eyes, skin and respiratory tract. It can cause blindness and permanent scarring.
Used in the manufacture of phosphate fertilizers and salts, superphosphates, polyphosphates, soaps and detergents, pharmaceuticals, activated carbon, animal feed, ceramics, dental cements, soft drinks, gelatin, food additives, rust inhibitors, fire-control agents, waxes and polishes, water treatment chemicals; acidulant and flavour agent; sequestering, metal complexing and stabilizing agent in food processing; bonding agent in refractory products; in electropolishing, lithography and photoengraving, printing, metal cleaning and sugar refining; in acidic hard-surface cleaning and sanitation formulations; wood and fabric flame proofing; opacity control in glass manufacture; textile dyeing; boiler cleaning; rubber latex coagulation; catalyst; laboratory reagent.
Phosphoric acid is available in aqueous solution in concentrations ranging from 33 to 85 percent, with 75, 80 and 85% being the most common. Pure anhydrous phosphoric acid forms a hemihydrate (CAS 16271-20-8).
Phosphoric acid is also known as orthophosphoric acid, o-phosphoric acid, white phosphoric acid, acide phosphorique.
Its CAS Registry Number is 7664-38-2. This number is assigned by the Chemical Abstracts Service (CAS) in the United States and is used as a unique identifier number world-wide.
Document last updated on February 19, 1999
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