Phosphate ions oxidation

Other Salts. Indium nitrate trihydrate [13770-61 -1], In(N02)3 3H20, is a soluble salt prepared by dissolution of the metal or oxide in nitric acid. Indium phosphate [14693-82-4], InPO, is precipitated by adding phosphate ions to a solution of an indium salt. It is soluble in water. 

The bath components for a nitrite—nitrate accelerated bath basic to this conversion coating process are (/) 2inc metal or 2inc oxide dissolved in acid (2) phosphate ions added as phosphoric acid (J) addition of an oxidant such as sodium nitrite and (4) addition of nitric acid. Other oxidants such as peroxide, chlorate, chlorate in combination with nitrate, or an organic nitro compound may also be used. 

What is the oxidation number of phosphorus in sodium phosphite, Na3P03 In the dihydrogen phosphate ion ... 

Iron(Il) hydrogen phosphite, FeHPO, is oxidized by hypochlorite ions in basic solution. The products are chloride ion, phosphate ion, and iron(lll) hydroxide. Write the balanced equation for each half-reaction and the overall equation for the reaction. 

The rate of formation of sulphoxides from sulphides and iodine in aqueous solution has been found to be relatively slow. It may be, however, accelerated by certain nucleophiles, such as phthalate ion S hydrogen phosphate ion and E(-cyclodextrin phosphate ion . The selective oxidation of JV-acetylmethionine and N-acetylmethionine methyl ester to the corresponding S-oxides was achieved using iodine in the presence of dicarboxylate ions. 

The theory of the accumulation of the Gibbs energy of oxidation of carbonaceous substrates in the form of the bond of the phosphate ion to... 

Takahashi et a/.,79 in their work on the structure of the barrier layer [cf. Section IV(2)], have considered phosphate ions, which are found in the outer layer of the oxide, as immobile markers and, from the position of the boundary between the outer and the inner layer, deduced the transport number of the cation to vary between 0.73 and 0.81 in the current density range between 0.05 and 10 mA/cm 2. 

Relaxation studies have shown that the attachment of an ion to a surface is very fast, but the establishment of equilibrium in wel1-dispersed suspensions of colloidal particles is much slower. Adsorption of cations by hydrous oxides may approach equilibrium within a matter of minutes in some systems (39-40). However, cation and anion sorption processes often exhibit a rapid initial stage of adsorption that is followed by a much slower rate of uptake (24,41-43). Several studies of short-term isotopic exchange of phosphate ions between aqueous solutions and oxide surfaces have demonstrated that the kinetics of phosphate desorption are very slow (43-45). Numerous hypotheses have been suggested for this slow attainment of equilibrium including 1) the formation of binuclear complexes on the surface (44) 2) dynamic particle-particle interactions in which an adsorbing ion enhances contact adhesion between particles (43,45-46) 3) diffusion of ions into adsorbents (47) and 4) surface precipitation (48-50). 

Fig. 9. Precursor ion scan on an electrospray triple quadrupole mass spectrometer. From all the peptides present of the digested protein only those that are phosphorylated are detected in a precursor ion scan for the phosphate ion (P03, mass 79 Da) in negative ion mode. From the TPX protein three phosphorylated peptides could be detected Ml, AQLTM PSTPTVLK M2, LSETSVNTEQNSK and M3, VQPVQTTPSKDDVSNSATHVC DVK. M, Oxidized methionine C, carbamidomethylated cysteine.

Figure 2.8 The ATP/ADP cycle. The major ATP-generating process from fuel oxidation is oxidative phosphorylation driven by electron transport in the mitochondria. In muscle, the major energy-requiring process is physical activity. The phosphate ion is omitted from the figure for the sake of simplicity.

The tetrahedral phosphate ion PO43-, like the silicate ion with which it is isoelectronic, can form chains and networks, and indeed its parent oxide, a white, extremely hygroscopic solid commonly called phosphorus pentoxide (P2O5), consists of discrete P4O10 molecular units in which four PO4 units each share three corner oxygens such that the four P centers themselves form a tetrahedron. We customarily distinguish the following classes of phosphates ... 

Another important dietary mineral is phosphorus, which comes to us as the phosphate ion, H2P04. As you can see by checking back to Figure 13.26 on page 452, phosphate ions form the backbone of nucleic acids. In addition, they are components of the energy-packed compound adenosine triphosphate (ATP), shown in Figure 13.40, which is produced in the oxidation of carbohydrates, lipids, and proteins. 

Svoboda P, Harms-Ringdahl M (2002) Kinetics of phosphate-mediated oxidation of ferrous ion and formation of 8-oxo-2 -deoxyguanosine in solutions of free 2 -deoxyguanaosine and calf thymus DNA. Biochim Biophys Acta 1571 45-54... 

Let us analyze the ATP synthesis reaction (3.50), which, with respect to inorganic phosphate ion charge, requires one or two H+ ions for oxidation reaction. Figure 3.4 clearly illustrates that the H+-ATP-synthase responsible for oxidative phosphorylation consumes active H30+ particles (H+ ion) from both parts of the reaction system (matrix and cytoplasm). Specifying the work of H+-ATP-synthase, it should be noted that H+ ions delivered from the cytoplasm to the membrane and ADP and P substrates participate in phosphorylation reaction proceeding on the internal surface of the membrane. In this case, water molecules are one of the products of oxidative phosphorylation. It does not release to the volume, but dissociates to H + and OH ions immediately on the membrane. Then according to the chemiosmotic mechanism OH anion is desorbed to cytoplasm and H+ ion to the matrix, where its occurrence as the active particle is associated with water production at the final stage of the respiration process. 

Reactions of the same type are the anodic oxidation of thiosulphate, sulphite, carbonate and phosphate ions, proceeding according to overall equations ... 

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