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E338 (Phosphoric acid)

E338 (Phosphoric acid)

CAS NO.: 7664-38-2
EC/LIST NO.: 231-633-2phosphoric acid

E338 (Phosphoric acid) (orth), monophosphoric acid or phosphoric(V) acid), is a weak acid with the chemical formula H3PO4. 
The pure compound is a colorless solid.

All three hydrogens are acidic to varying degrees and can be lost from the molecule as H+ ions (protons). 
When all three H+ ions are removed, the result is an orthophosphate ion PO43−, commonly called "phosphate". 
Removal of one or two protons gives dihydrogen phosphate ion H2PO−4, and the hydrogen phosphate ion HPO2−4, respectively. 
ortohphosphoric acid also forms esters, called organophosphates. 

E338 (Phosphoric acid) is commonly encountered in chemical laboratories as an 85% aqueous solution, which is a colourless, odourless, and non-volatile syrupy liquid. 
Although E338 (Phosphoric acid) does not meet the strict definition of a strong acid, the 85% solution can still severely irritate the skin and damage the eyes.

The name "ortohphosphoric acid" can be used to distinguish this specific acid from other "E338 (Phosphoric acid)s", such as pyrophosphoric acid. 
Nevertheless, the term "E338 (Phosphoric acid)" often means this specific compound; and that is the current IUPAC nomenclature.

E338 (Phosphoric acid) is produced industrially by two general routes.
In the wet process a phosphate-containing mineral such as calcium hydroxyapatite is treated with sulfuric acid. 

E338 (Phosphoric acid) is an inorganic compound acid derived from the mineral phosphorus. 
E338 (Phosphoric acid) is a crystalline solid, but in its less concentrated form it is a colorless syrupy liquid. 
E338 (Phosphoric acid) is used to acidify foods and beverages, and serves as a starting point to produce many phosphate derivatives.

E338 (Phosphoric acid) is a colorless, odorless phosphorus-containing inorganic acid. 
E338 (Phosphoric acid) is a sequestering agent which binds many divalent cations, including Fe++, Cu++, Ca++, and Mg++.

E338 (Phosphoric acid) (PA) is an important industrial chemical used as an intermediate in the fertilizer industry, for metal surface treatment in the metallurgical industry and as an additive in the food industry. 
The PA industry is spread out worldwide in Europe, Asia and America, including countries that operate phosphate rock (PR) mines and produce PA, phosphatic fertilizers and phosphate-based products.

E338 (Phosphoric acid) is used in a wide array of applications including the manufacturing of phosphate salts.

In addition to being a chemical reagent, E338 (Phosphoric acid) Food Grade is used as an ingredient in foods and beverages. 
E338 (Phosphoric acid) is typically used for pH control in the food industry, for example in the manufacture of cheese products, fats, and shortenings.  
E338 (Phosphoric acid) is also used in the beverage industry in soft drinks, particularly cola. 

E338 (Phosphoric acid) Tech Grade is used in plant nutrition applications to provide precise and targeted fortification with water-soluble solutions.  

E338 (Phosphoric acid) is also used for water treatment, metal finishing, construction, and other industrial applications.

E338 (Phosphoric acid) is also known as ortohphosphoric acid and is classed as a weak acid.
Austenitic stainless steels have good corrosion resistance to chemically pure E338 (Phosphoric acid).
Wet process E338 (Phosphoric acid) (WPA) can be aggressive.

E338 (Phosphoric acid) is used as a chemical-cleaning agent for stainless steels but is not considered to be a ‘passivating’ acid.

Commercially concentrated acid is around 85wt. %

E338 (Phosphoric acid) (H3PO4) is the leading inorganic acid produced and consumed in terms of production value and it is the second largest in terms of volume—after sulfuric acid. 
By far its greatest use is in the manufacture of phosphate chemicals consumed primarily as carriers of phosphorus values in fertilizers.
Use in the production of animal feeds is of secondary importance. 
E338 (Phosphoric acid) is also used in the manufacture of phosphate chemicals for use in water treatment and detergent builders, dentifrices, fire control chemicals, and a host of smaller markets. 
Consumption of E338 (Phosphoric acid) for its acid properties is relatively small (e.g., treatment of metal surfaces, beverage acidulation). 
E338 (Phosphoric acid) is the leading intermediate product or processing step between phosphate rock and the end markets for phosphorus in phosphate form.

The supply/demand balance for E338 (Phosphoric acid) is supply driven. 
If all the announced projects materialize, operating rates will improve. 
Emerging regions are heavily investing in downstream phosphate fertilizer production units. 
As a result, E338 (Phosphoric acid) is expected that older E338 (Phosphoric acid) production units in regions without indigenous phosphate rock reserves will come under additional pressure and will eventually be forced to close.

E338 (Phosphoric acid), H3PO4, is a strong acid used commonly for industrial purposes. 
Dilute solutions have been used to acidify urine and as an aid to remove necrotic debris. 
In dentistry, it may be used in silicate cements, and to etch enamel and dentin surfaces prior to application of various types of resins. 
In may also be used as a dispersing agent in pharmaceuticals. 
The primary use of E338 (Phosphoric acid) is in fertilizers. 

E338 (Phosphoric acid), also known as ortohphosphoric acid, is a weak acid. 
E338 (Phosphoric acid) is available in a range of purities, reagent grades, and quantities. 
E338 (Phosphoric acid) has a variety of applications in food and manufacturing and can be used as an external standard for phosphorus-31 NMR studies.

Phosphorus is an essential plant nutrient and is taken up by plant roots, usually as the dihydrogenphosphate ion, H2PO4-, derived from E338 (Phosphoric acid), H3PO4.  
The manufacture of fertilizers that are used to rectify phosphorus deficiencies in soils depends on the availability of supplies of E338 (Phosphoric acid).

E338 (Phosphoric acid) is a colorless, odorless mineral acid. 
With an acidic taste and somewhat viscous consistency, E338 (Phosphoric acid) is used in a wide variety of products and industries. 
Despite its popularity, this chemical can pose some potentially significant health hazards and should be handled with caution.

You are composed of all sorts of organic molecules. 
That doesn't mean those molecules are labeled with a sticker that says 'organic'. 
E338 (Phosphoric acid) means these molecules contain carbon. 
But not everything on Earth is organic. 
Some things lack carbon. 
Such substances are commonly referred to as being inorganic. 
One of them is E338 (Phosphoric acid), a corrosive inorganic acid.

You're about to learn a bit more about its structure, formula, properties and uses.

{displaystyle {ce {Ca5(PO4)3OH + 5H2SO4 -> 3H3PO4 + 5CaSO4v + H2O}}}{displaystyle {ce {Ca5(PO4)3OH + 5H2SO4 -> 3H3PO4 + 5CaSO4v + H2O}}}
Fluoroapatite is an alternative feedstock, in which case fluoride is removed as the insoluble compound Na2SiF6. 
The E338 (Phosphoric acid) solution usually contains 23–33% P2O5 (32–46% H3PO4). 
It may be concentrated to produce commercial- or merchant-grade E338 (Phosphoric acid), which contains about 54–62% P2O5 (75–85% H3PO4). 
Further removal of water yields superE338 (Phosphoric acid) with a P2O5 concentration above 70% (corresponding to nearly 100% H3PO4). 
Calcium sulfate (gypsum) is produced as a by-product and is removed as phosphogypsum.

To produce food-grade E338 (Phosphoric acid), phosphate ore is first reduced with coke in an electric arc furnace, to make elemental phosphorus. 
Silica is also added, resulting in the production of calcium silicate slag. 
Elemental phosphorus is distilled out of the furnace and burned with air to produce high-purity phosphorus pentoxide, which is dissolved in water to make E338 (Phosphoric acid).

The E338 (Phosphoric acid) from both processes may be further purified by removing compounds of arsenic and other potentially toxic impurities.

Food-grade E338 (Phosphoric acid) (additive E338[19]) is used to acidify foods and beverages such as various colas and jams, providing a tangy or sour taste. 
The E338 (Phosphoric acid) also serves as a preservative.
Soft drinks containing E338 (Phosphoric acid), which would include Coca-Cola, are sometimes called phosphate sodas or phosphates. 
E338 (Phosphoric acid) in soft drinks has the potential to cause dental erosion.
E338 (Phosphoric acid) also has the potential to contribute to the formation of kidney stones, especially in those who have had kidney stones previously. 

Specific applications of E338 (Phosphoric acid) include:

in anti-rust treatment by phosphate conversion coating or passivation
to prevent iron oxidation by means of the Parkerization process
as an external standard for phosphorus-31 nuclear magnetic resonance
in E338 (Phosphoric acid) fuel cells
in activated carbon production 
in compound semiconductor processing, to etch Indium gallium arsenide selectively with respect to indium phosphide 
in microfabrication to etch silicon nitride selectively with respect to silicon dioxide 
as a pH adjuster in cosmetics and skin-care products 
as a sanitizing agent in the dairy, food, and brewing industries 

E338 (Phosphoric acid) is a colorless, odorless phosphorus-containing inorganic acid. 
E338 (Phosphoric acid) is a sequestering agent which binds many divalent cations, including Fe++, Cu++, Ca++, and Mg++. 
E338 (Phosphoric acid) is used in dentistry and orthodontics as an etching solution, to clean and roughen the surfaces of teeth where dental appliances or fillings will be placed. 
In addition, E338 (Phosphoric acid) is a constituent in bone and teeth, and plays a role in many metabolic processes.

E338 (Phosphoric acid) appears as a clear colorless liquid or transparent crystalline solid. 
The pure solid melts at 42.35°C and has a density of 1.834 g / cm3. 
Liquid is usually an 85% aqueous solution. 
Shipped as both a solid and liquid. 
Corrosive to metals and tissue. 
Used in making fertilizers and detergents and in food processing.

E338 (Phosphoric acid) is a phosphorus oxoacid that consists of one oxo and three hydroxy groups joined covalently to a central phosphorus atom. 
E338 (Phosphoric acid) has a role as a solvent, a human metabolite, an algal metabolite and a fertilizer. 
E338 (Phosphoric acid) is a conjugate acid of a dihydrogenphosphate and a phosphate ion.

E338 (Phosphoric acid) is a colorless, odorless crystalline liquid. 
E338 (Phosphoric acid) gives soft drinks a tangy flavor and prevents the growth of mold and bacteria, which can multiply easily in a sugary solution. 
Most of soda’s acidity also comes from E338 (Phosphoric acid).

E338 (Phosphoric acid) is made from the mineral phosphorus, which is found naturally in the body. 
E338 (Phosphoric acid) works with calcium to form strong bones and teeth. 
E338 (Phosphoric acid) also helps support kidney function and the way your body uses and stores energy. 
Phosphorus helps your muscles recover after a hard workout. 
The mineral plays a major role in the body’s growth and is even needed to produce DNA and RNA, the genetic codes of living things.

Phosphorus is first turned to phosphorus pentoxide through a chemical manufacturing process. 
E338 (Phosphoric acid) then treated again to become E338 (Phosphoric acid).

E338 (Phosphoric acid) is used in the manufacture of superphosphate fertilisers, livestock feeds, phosphate salts, polyphosphates, soaps, waxes, polishes and detergents. 
E338 (Phosphoric acid) is used as a soil stabiliser, in the manufacture of fire control agents, opal glasses, electric lights, in cotton dyeing, tile cleaning, ceramic binding, dental cement, water treatment, electro-polishing, operating lithography, photoengraving operations, process engraving, as a petrol additive and in coagulating rubber latex. 
E338 (Phosphoric acid) is used in metal rust proofing before painting, in the polishing of metals, in pickling and in hot stripping for aluminium and zinc substrates. 
E338 (Phosphoric acid) is used as an acid catalyst in making ethylene and purifying hydrogen peroxide, in the manufacture of chemicals (ethylbenzene, propylene, cumene), as a bonding agent for refractory bricks, in extracting penicillin and as an analytical agent. 
E338 (Phosphoric acid) is used as an anti-oxidant in food, as a flavour additive for sharp taste in food (jellies, preserves) and soft drinks (e.g. Coca-Cola), as a tang (Food Additive 338) and for the manufacture of yeasts and gelatine. 
E338 (Phosphoric acid) is used to manufacture the E338 (Phosphoric acid) electrolyte fuel cell system and it has been used to treat lead poisoning.

Boiling point    158 °C (1013 mbar)
Density    1.71 g/cm3 (20 °C)
Melting Point    21 °C
pH value    <0.5 (100 g/l, H₂O, 20 °C)
Vapor pressure    2 hPa (20 °C)
Viscosity kinematic    30.5 mm2/s (20 °C)

E338 (Phosphoric acid) is produced by the reaction of fluorapatite known as 'phosphate rock' 3Ca3 (PO4) 2.CaF2 with sulfuric acid. 
E338 (Phosphoric acid) is a chemical that appeals to different sectors and has many uses. 
E338 (Phosphoric acid) is the main raw material input of phosphate fertilizer production. 
E338 (Phosphoric acid) is mostly used in the production of phosphate fertilizers, the pharmaceutical industry, agriculture, metal cleaning, polishing and food for acidity regulation.
The monograph also details the following specifications and corresponding tests for verifying that a substance meets ACS Reagent Grade specifications including: Assay, Color (APHA), Insoluble Matter, Chloride, Nitrate, Sulfate, Volatile Acids, Antimony, Calcium, Magnesium, Potassium, Sodium, Arsenic, Heavy Metals, Iron, Manganese, and Reducing Substances.

(also known as ortohphosphoric acid or phosphoric(V) acid) is a weak acid with the chemical formula H3PO4. 
ortohphosphoric acid refers to E338 (Phosphoric acid), which is the IUPAC name for this compound. 
The prefix ortho- is used to distinguish the acid from related E338 (Phosphoric acid)s, called polyE338 (Phosphoric acid)s. 
ortohphosphoric acid is a non-toxic acid, which, when pure, is a solid at room temperature and pressure. 
The conjugate base of E338 (Phosphoric acid) is the dihydrogen phosphate ion, H2PO−4, which in turn has a conjugate base of hydrogen phosphate, HPO2−4, which has a conjugate base of phosphate, PO3−4. 
Phosphates are essential for life. 

The most common source of E338 (Phosphoric acid) is an 85% aqueous solution; such solutions are colourless, odourless, and non-volatile. 
The 85% solution is a syrupy liquid, but still pourable. 
Although E338 (Phosphoric acid) does not meet the strict definition of a strong acid, the 85% solution is acidic enough to be corrosive. 
Because of the high percentage of E338 (Phosphoric acid) in this reagent, at least some of the ortohphosphoric acid is condensed into polyE338 (Phosphoric acid)s; for the sake of labeling and simplicity, the 85% represents H3PO4 as if it were all in the ortho form. 
Dilute aqueous solutions of E338 (Phosphoric acid) exist in the ortho form.

E338 (Phosphoric acid), any one of three chemical compounds made up of phosphorus, oxygen, and hydrogen (see acids and bases). 
The most common, ortohphosphoric acid, H3PO4, is usually simply called E338 (Phosphoric acid).
Two molecules of it are formed by adding three molecules of water, H2O, to one molecule of phosphorus pentoxide (phosphoric anhydride, P2O5). 
E338 (Phosphoric acid) occurs as rhombic crystals or as a viscous liquid; both are deliquescent. 
The crystals melt at about 42°C. 
E338 (Phosphoric acid) has specific gravity 1.834 at 18°C, is soluble in alcohol, and is very soluble in water. 
E338 (Phosphoric acid) is a tribasic acid and forms orthophosphate salts with either one, two, or all three of the hydrogens replaced by some other positive ion. 
When it is heated to about 225°C, it dehydrates to form pyroE338 (Phosphoric acid), H4P2O7; at still higher temperatures metaE338 (Phosphoric acid), HPO3, is formed. 
Salts of pyroE338 (Phosphoric acid) are pyrophosphates; salts of metaE338 (Phosphoric acid) are metaphosphates. 
E338 (Phosphoric acid) is prepared commercially by heating calcium phosphate rock with sulfuric acid; purer grades may be prepared by treating red phosphorus with nitric acid. 
E338 (Phosphoric acid) is used in pickling and rust-proofing metals, in acidifying jellies and beverages, and in preparing phosphate salts.


1921286 [Beilstein]
231-633-2 [EINECS]
7664-38-2 [RN]
Acide phosphorique [French] [ACD/IUPAC Name]
Acido fosforico [Spanish]
Acido fosforico [Italian]
Acidum phosphoricum [Latin]
Fosforzuuroplossingen [Dutch]

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