PyroPhosphoric add

It will be observed that ordinary phosphorous acid may be regarded as ortho-phosphorous acid, P(0H)3, which has undergone some intramolecular change, forming H—P0=(0H)2 if the meta-acid is regarded as a derivative of the ortho-acid by the loss of water, then the condensation of two mols of the ortho-acid, with the loss of water, will furnish normal pyrophosphorous add, H4P205 ... 

The hydration of pyrophosphoric add.—T. Graham kept an aq. soln. of dil. pyrophosphoric acid for six months without change but, when heated, it was converted into the ortho-acid. The hydration of dil. soln. of pyrophosphoric acid is therefore slow at ordinary temp., but it is rapid when boiled. M. Berthelot and G. Andre 4 found that a soln. of pyrophosphoric acid contained after standing ... 

A number of license holders, induding UOP, have proposed the industrial use of phosphoric add deposited on a support Operations in this case are conducted around 250 C, at a pressure of 8.10 Pa. The water content of the reaction meriitim must be kept at an optimum value, since any excess leads to entrainment of the add, and a defidency to the deactivation of the catalyst by the formation of pyrophosphoric add. 

Note Like sulfuric acid (. v.) o/tho-phosphoric add is a universal reagent, with which almost all classes of substance can be detected at high temperatures (ISO-180 °C) by charring e.g. high molecular weight hydrocarbons (mineral oils) [20]. The colors and fluorescences produced at lower temperatures (<120°C) and their intensities are very dependent on the temperature and period of heating. It is not possible to use meta- or pyrophosphoric acid in place of o/tAo-phosphoric add, since, for instance, amanita toxins react well with alcoholic phosphoric add only weakly with aqueous phosphoric add and not at all with meta- or pyrophosphoric add [17]. 

Write a balanced equation for each of the following reactions (a) hydrolysis of PCI5, (b) dehydration of phosphoric acid (also called orthophosphoric acid) to form pyrophosphoric add, (c) reaction of P4O 0 with water. 

UNC Recovery Corp. developed a sir le-stage process that uses an alkyl pyrophosphoric add extractant this -proeess-was-intended for-commercial use by Prodeco Inc., a wholly-owned subsidiary. 

Esters of pyrophosphorous add can be prepared by using sodium dialkyl phosphite and a dialkyl phosphorochloridite (5.321). If a phosphorochloridate ester is used, an ester of hypophosphoric acid is obtained (5.322). 

This add appears to be the gladal phosphoric acid, which had been hastily as-stimed by recent writers upon this subject to be the pyrophosphoric add, but is totally different. I shall take the liberty to designate provisionally the add of the fused biphosphate of soda, the Metaphosphoric add, from an hypothesis of its constitution, to be immediately explained and the fused salt itself, the Metaphosphate of soda. 

How is rubber made in nature Plants construct the polyisoprene framework of natural rubber by using as a building block 3-methyl-3-butenyl pyrophosphate (isopentenyl pyrophosphate). This molecule is an ester of pyrophosphoric add and 3-methyl-3-buten-l-ol. An enzyme equilibrates a small amount of this material with the 2-butenyl isomer, an aUylic pyrophosphate. 

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