Phosphate

A phosphate, in inorganic chemistry, is a salt of phosphoric acid. Inorganic chemistry is the branch of Chemistry concerned with the properties and behavior of Inorganic compounds This field covers all Chemical compounds A salt, in Chemistry, is defined as the product formed from the neutralisation reaction of Acids and bases. Phosphoric acid, also known as orthophosphoric acid or phosphoric(V acid, is a mineral (inorganic acid having the Chemical formula Inorganic phosphates are mined to obtain phosphorus for use in industry. Mining is the extraction of valuable Minerals or other geological materials from the earth usually (but not always from an Ore body Phosphorus, (ˈfɒsfərəs is the Chemical element that has the symbol P and Atomic number 15 ^[1] ^[2] In organic chemistry, a phosphate, or organophosphate, is an ester of phosphoric acid. Organic chemistry is a discipline within Chemistry which involves the scientific study of the structure properties composition reactions, and preparation An organophosphate (sometimes abbreviated OP) is the general name for Esters of Phosphoric acid. Esters are a class of Chemical compounds and Functional groups Esters consist of an inorganic or organic Acid in which at least Organic phosphates are important in biochemistry and biogeochemistry. Biochemistry is the study of the chemical processes in living Organisms It deals with the Structure and function of cellular components such as The field of biogeochemistry involves scientific study of the chemical, physical, geological, and biological processes and reactions

1 Chemical properties
2 Cellular function
3 See also
4 Further reading
5 References
6 External links

Chemical properties

The general chemical structure of a phosphate

This is the structural formula of the phosphoric acid functional group as found in a weakly acidic aqueous solution. The structural formula of a Chemical compound is a graphical representation of the molecular structure showing how the atoms are arranged In Organic chemistry, functional groups are specific groups of Atoms within Molecules that are responsible for the characteristic Chemical reactions In Computer science, ACID ( Atomicity Consistency Isolation Durability) is a set of properties that guarantee that Database transactions are In more basic aqueous solutions, the group donates the two hydrogen atoms and ionizes as a phosphate group with a negative charge of 2. In Chemistry, a base is most commonly thought of as an aqueous substance that can accept Protons This refers to the Brønsted-Lowry theory of acids and Hydrogen (ˈhaɪdrədʒən is the Chemical element with Atomic number 1 History See also Atomic theory, Atomism The concept that matter is composed of discrete units and cannot be divided into arbitrarily tiny An ion is an Atom or Molecule which has lost or gained one or more Valence electrons giving it a positive or negative electrical charge ^[3]

The phosphate ion is a polyatomic ion with the empirical formula P O₄³⁻ and a molar mass of 94. A polyatomic ion is a charged species ( Ion) composed of two or more atoms covalently bonded or of a metal complex that can be considered as acting Use in chemistry In Chemistry, the empirical formula of a Chemical compound is a simple expression of the relative number of each type of Atom Phosphorus, (ˈfɒsfərəs is the Chemical element that has the symbol P and Atomic number 15 Oxygen (from the Greek roots ὀξύς (oxys (acid literally "sharp" from the taste of acids and -γενής (-genēs (producer literally begetteris the Molar mass, symbol M, is the Mass of one mole of a substance ( Chemical element or Chemical compound) 973 g/mol; it consists of one central phosphorus atom surrounded by four identical oxygen atoms in a tetrahedral arrangement. Phosphorus, (ˈfɒsfərəs is the Chemical element that has the symbol P and Atomic number 15 A tetrahedron (plural tetrahedra) is a Polyhedron composed of four triangular faces three of which meet at each vertex. The phosphate ion carries a negative three formal charge and is the conjugate base of the hydrogenphosphate ion, HPO₄²⁻, which is the conjugate base of H₂PO₄⁻, the dihydrogen phosphate ion, which in turn is the conjugate base of H₃PO₄, phosphoric acid. Within the Brønsted - Lowry ( protonic) theory of acids and bases, a conjugate acid is the acid member HX of a pair of two compounds that transform Phosphoric acid, also known as orthophosphoric acid or phosphoric(V acid, is a mineral (inorganic acid having the Chemical formula It is a hypervalent molecule (the phosphorus atom has 10 electrons in its valence shell). A hypervalent molecule is a Molecule that contains one or more typical elements ( group 1 2 13-18 formally bearing more than eight Electrons in their An electron shell may be crudely thought of as an Orbit followed by Electrons around an Atom nucleus. Phosphate is also an organophosphorus compound with the formula OP(OR)₃

A phosphate salt forms when a positively-charged ion attaches to the negatively-charged oxygen atoms of the ion, forming an ionic compound. Organophosphorus compounds are Chemical compounds containing Carbon - Phosphorus bonds. A chemical compound is a substance consisting of two or more different elements chemically bonded together in a fixed proportion by Mass. Many phosphates are not soluble in water at standard temperature and pressure. Solubility is the characteristic Physical property referring to the ability of a given substance the Solute, to dissolve in a Solvent. Water is a common Chemical substance that is essential for the survival of all known forms of Life. In Physical sciences standard conditions for temperature and pressure are Standard sets of conditions for experimental measurements to allow comparisons to be made

In dilute aqueous solution, phosphate exists in four forms. In strongly-basic conditions, the phosphate ion (PO₄³⁻) predominates, whereas in weakly-basic conditions, the hydrogen phosphate ion (HPO₄²⁻) is prevalent. In weakly-acid conditions, the dihydrogen phosphate ion (H₂PO₄⁻) is most common. In strongly-acid conditions, aqueous phosphoric acid (H₃PO₄) is the main form.

H₃PO₄

H₂PO₄⁻

HPO₄²⁻

PO₄³⁻

More precisely, considering the following three equilibrium reactions:

H₃PO₄ ⇌ H⁺ + H₂PO₄⁻

H₂PO₄⁻ ⇌ H⁺ + HPO₄²⁻

HPO₄²⁻ ⇌ H⁺ + PO₄³⁻

the corresponding constants at 25°C (in mol/L) are (see phosphoric acid):

$K_{a1}=\frac{[\mbox{H}^+][\mbox{H}_2\mbox{PO}_4^-]}{[\mbox{H}_3\mbox{PO}_4]}\simeq 7.5\times10^{-3}$

$K_{a2}=\frac{[\mbox{H}^+][\mbox{HPO}_4^{2-}]}{[\mbox{H}_2\mbox{PO}_4^-]}\simeq 6.2\times10^{-8}$

$K_{a3}=\frac{[\mbox{H}^+][\mbox{PO}_4^{3-}]}{[\mbox{HPO}_4^{2-}]}\simeq 2.14\times10^{-13}$

For a strongly-basic pH (pH=13), we find

$\frac{[\mbox{H}_2\mbox{PO}_4^-]}{[\mbox{H}_3\mbox{PO}_4]}\simeq 7.5\times10^{10} \mbox{ , }\frac{[\mbox{HPO}_4^{2-}]}{[\mbox{H}_2\mbox{PO}_4^-]}\simeq 6.2\times10^5 \mbox{ , } \frac{[\mbox{PO}_4^{3-}]}{[\mbox{HPO}_4^{2-}]}\simeq 2.14$

showing that only PO₄³⁻ and HPO₄²⁻ are in significant amounts. Phosphoric acid, also known as orthophosphoric acid or phosphoric(V acid, is a mineral (inorganic acid having the Chemical formula

For a neutral pH (for example the cytosol pH=7. 0), we find

$\frac{[\mbox{H}_2\mbox{PO}_4^-]}{[\mbox{H}_3\mbox{PO}_4]}\simeq 7.5\times10^4 \mbox{ , }\frac{[\mbox{HPO}_4^{2-}]}{[\mbox{H}_2\mbox{PO}_4^-]}\simeq 0.62 \mbox{ , } \frac{[\mbox{PO}_4^{3-}]}{[\mbox{HPO}_4^{2-}]}\simeq 2.14\times10^{-6}$

so that only H₂PO₄⁻ and HPO₄²⁻ ions are in significant amounts (62% H₂PO₄⁻, 38% HPO₄²⁻). Note that in the extracellular fluid (pH=7. 4), this proportion is inverted (61% HPO₄²⁻, 39% H₂PO₄⁻).

For a strongly-acid pH (pH=1), we find

$\frac{[\mbox{H}_2\mbox{PO}_4^-]}{[\mbox{H}_3\mbox{PO}_4]}\simeq 0.075 \mbox{ , }\frac{[\mbox{HPO}_4^{2-}]}{[\mbox{H}_2\mbox{PO}_4^-]}\simeq 6.2\times10^{-7} \mbox{ , } \frac{[\mbox{PO}_4^{3-}]}{[\mbox{HPO}_4^{2-}]}\simeq 2.14\times10^{-12}$

showing that H₃PO₄ is dominant with respect to H₂PO₄⁻. HPO₄²⁻ and PO₄³⁻ are practically absent.

Phosphate can form many polymeric ions such as diphosphate (also pyrophosphate), P₂O₇⁴⁻, and triphosphate, P₃O₁₀⁵⁻. In Chemistry, the Anion, the Salts and the Esters of Pyrophosphoric acid are called pyrophosphates. In Chemistry, the Anion, the Salts and the Esters of Pyrophosphoric acid are called pyrophosphates. The various metaphosphate ions have an empirical formula of PO₃⁻ and are found in many compounds. A metaphosphate is a salt or an ester of metaphosphoric acid HPO3

Phosphate deposits can contain significant amounts of naturally occurring uranium. Uranium (jʊˈreɪniəm is a silvery-gray Metallic Chemical element in the Uptake of these substances by plants can lead to high uranium concentrations in crops.

Cellular function

Phosphate is useful in animal cells as a buffering agent. For an aqueous solution composed of both a weak acid or base and its conjugate see Buffer solution. The kinds of phosphate that are useful as buffers include NaH₂PO₄^- and H₂PO₄^-.

References

^ Phosphate Primer, website of the Florida Institute of Phosphate Research
^ "Figuring Out Phosphates," Food Product Design, June 2006, Lynn A. Kuntz
^ Campbell, Neil A.; Reece, Jane B. Neil Campbell may refer to Sir Neil Campbell (known as Niall mac Cailein, d (2005). Biology, Seventh Edition, San Francisco, California: Benjamin Cummings, 65. The City and County of San Francisco is the fourth most populous city ISBN 0-8053-7171-0.

External links

Website of the Technische Universität Darmstadt and the CEEP about Phosphorus Recovery

Dictionary

-noun

(chemistry) Any salt or ester of phosphoric acid.

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Contents

Chemical properties

Cellular function

See also

Further reading

References

External links

Dictionary

phosphate

-noun