Diphosphorous acid pyrophosphorous

Two examples of condensed phosphoricfV) acids are heptaoxo-diphosphoric(V) (pyrophosphoric) and polytrioxophosphoric (meta-phosphoric) acids. 

Pyrophosphoric (diphosphoric) acid, H4P2O2, is the only condensed phosphoric acid definitely obtainable ia crystalline form. It has a theoretical P2O5 content of 79.8%. However, Hquid polyphosphoric acid of such content shows by analysis only 42.5% the remainder is phosphoric acid and... 

H4P2O5 (2)C > Diphosphonic acid (diphosphorous or pyrophosphorous acid)... 

HP03/ which is known as metaphosphoric acid, and it is a strong acid. We can view the formation of ff4P207 (known as diphosphoric acid or pyrophosphoric acid) as arising from the addition of P205 to ff3P04 or the removal of a molecule of water from two molecules of H3P04. The first process can be shown as... 

A feature of phosphoric acid is that it forms a series of poiymeric anhydrides that resembie carboxyiic acid anhydrides in structure and reactivity. Diphosphoric acid (formeriy caiied pyrophosphoric... 

Pyrophosphate (also known as diphosphate) or 1 207" . The conjugate base of pyrophosphoric acid (or, diphosphoric acid), H4P2O7 (having pi a values, at 25°C, of 0.85, 1.96, 6.60, and 9.41). Crystals of tetrasodium pyrophosphate (mp = 988°C) are very soluble in water. The pyrophosphate anion hydrolyzes to orthophosphate however, the rate of hydrolysis is much slower than that of pyrophosphoric acid. The hydrated form of tetrasodium pyrophosphate exhibits a shght degree of efflorescence. 

Oisodium dihydrogen pyrophosphate Pyrophosphoric acid, disodium salt (8) Diphosphoric acid, disodium salt (9) (7758-16-9)... 

Pyrophosphoric acid (also known as diphosphoric acid), H4P207, has a mole ratio of H20/P205 of 2. The equation for its preparation can be written as... 

When orthophosphoric acid is heated it loses water and condenses to diphosphoric acid or pyrophosphoric acid, H4P0O7 ... 

Dolichols are a family of long-chain polyisoprenols that occur only in eukaryotes. They are related in structure and function to undecaprenyl phosphate, a prokaryotic polyisoprenol used in the synthesis of peptido-glycan (see below). Dolichols contain 65-110 carbons arranged as 13-22 isoprene units, two in the trans configuration, the remainder in the cis configuration. The initial isoprene unit is saturated and carries a hydroxyl group, which is esterified with orthophosphoric (monophosphoric) or pyrophosphoric (diphosphoric) acid in dolichol phosphate and pyrophosphate, respectively (Figure 16-6). 

Anhydrous tetrasodium pyrophosphate Caswell No. 847 Diphosphoric acid, tetrasodium salt EINECS 231-767-1 EPA Pesticide Chemical Code 0764()5 HSDB 854 Natrium pyrophosphat NSC 56751 Phosphotex Pyrophosphoric acid, tetrasodium salt Sodium diphosphate (Na4P20 ) Sodium diphosphate, anhydrous Sodium phosphate (Na4P207) Sodium pyrophosphate Sodium pyrophosphate, tetrabasic ... 

Phosphorus is capable of making many different oxoacids of which some of most important are orthophosphoric acid, Ff3P04. diphosphoric acid, 4 207, which is a dimeric example of the series of orthophosphoric acid anhydrates called pyrophosphoric acid. Metaphosphoric acid is a polymeric form of phosphorous acid, HPOg. Since these substances, and the other oxoacids, are unstable and fairly easily convert into orthophosphoric acid is by far the most widely encountered, and for the same reason it is normally referred to as just phosphoric acid without the prefix ortho. 

Synonyms Bis-0,0-diethylphosphoric anhydride Diphosphoric acid, tetraethyl ester Ethyl pyrophosphate, tetra- Pyrophosphoric acid, tetraethyl ester TEP TEPP Tetraethyl diphosphate Tetraethylpyrophosphate Classification Phosphoric acid ester Empirical C8H20O7P2... 

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