Hydrogen phosphate ions

H2po.r Dihydrogen phosphate ion 7.21 HP042 Hydrogen phosphate ion... 

Dihydrogen phosphate ion (ftPOr) Hydrogen phosphate ion (HP042-) 6.2 X 10-8 7.21... 

As a third and final example of a chain reaction, we shall consider a net reaction that produces sulfate and hydrogen phosphate ions.7 The scheme is more intricate than the earlier ones. It starts with the homolytic dissociation of S2Ojj- as one of two parallel initiation steps, and utilizes SO -, HO, and HPO - as intermediates. The scheme suggested is shown here, and one can easily allow for the products that are identical save for protonation ... 

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. 

IB (a) Provided [OH ] is not too high, the hydrogen phosphate ion is not expected to ionize in aqueous solution to a significant extent because of the quite small values for the second and third ionization constants of phosphoric acid. 

Now imagine adding some acid to the solution - either by mistake or deliberately. Clearly, the concentration of H+ will increase. To prevent the value of Ka changing, some of the hydrogen phosphate ions combine with the additional protons to form dihydrogen phosphate (i.e. Equation (6.48) in reverse). The position of the equilibrium adjusts quickly and efficiently to mop up the extra protons in the buffer solution. In summary, the pH is prevented from changing because protons are consumed. 

Phosphates have been formed by slow hydrolysis of trialkyl phosphates, hydrogen phosphate ions, or metaphosphoric acid, which liberate phosphate ions (see p. 46 in Ref. 31). This may be of interest as a precursor for the preparation of phosphide semiconductors. 

Species in solution containing the PO4 species of the orthophosphates, using the ferric salts FeCl3 and Fe2(S04)3 as precipitants Milligrams per liter of snspended sohds in raw water Cubic meters of water treated Water of hydration of alnm Activity coefficient of the calcium ion Activity coefhcient of the hydrogen ion Activity coefhcient of the hydrogen phosphate ion Activity coefhcient of the dihydrogen phosphate ion Activity coefhcient of the phosphate ion... 

One way in which photosynthetic bacteria store chemical energy is through the conversion of a compound called adenosine diphosphate (ADP), together with hydrogen phosphate ion, to adenosine triphosphate (ATP) ... 

Hydrolysis of meperidine hydrochloride in dilute hydrochloric acid is a specific hydronium ion catalyzed reaction which is first order with respect to hydrogen ion concentration. A positive, primary salt effect was noted in dilute acid solution. The hydrolysis of the protonated form of meperidine hydrochloride was found to be first order with respect to meperidine hydrochloride over a wide range of hydrogen ion concentration (pH 1-7) A catalytic effect with respect to meperidine hydrolysis was exhibited by di-hydrogen phosphate ion, the only phosphate ion studied in the investigation, and the possibility of similar effects with respect to other buffer systems should be recognized. The rate of hydrolysis was found to be very slow in the pH range of 3.5 to 5 with maximum stability at pH U.01. The calculated half-life for meperidine hydrochloride at pH U.9 is 23.8 years at 25 °C. 

H3PO4 phosphoric acid H2PO4 HPO42 PO43 dihydrogen phosphate ion hydrogen phosphate ion phosphate ion... 

HP04 is hydrogen phosphate ion. H2P04 is dihydrogen phosphate ion. 

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