Search results for "Hydrolysis constant"
showing 4 items of 4 documents
Hydrolysis and chemical speciation of dioxouranium(VI) ion in aqueous media simulating the major ion composition of seawater
2004
Abstract The hydrolysis and chemical speciation of the dioxouranium(VI) ion at 25 °C was studied in a number of binary electrolytes (LiCl, NaCl, MgCl2, CaCl2, Na2SO4) and some mixtures (NaCl–Na2SO4, NaNO3–Na2SO4, CaCl2–MgCl2) as well as artificial seawater (SSWE) as a function of ionic strength. The results in LiCl, CaCl2 and MgCl2 solutions confirmed the formation of (UO2)2(OH)22+, (UO2)3(OH)42+, (UO2)3(OH)5+ and (UO2)3(OH)7− species (at I=0 mol l−1: log Tβ22=−5.76, log Tβ34=−11.82, log Tβ35=−15.89 and log Tβ37=−29.26). For NaNO3, NaCl and artificial seawater the hydrolysis constant for the formation of the UO2(OH)+ species was also determined (at I=0 mol l−1: log Tβ11=−5.19). The results …
Speciation of Al3+ in fairly concentrated solutions (20 to 200 mmol L-1) at I = 1 mol L-1 (NaNO3), in the acidic pH range, at different temperatures.
2011
AbstractThe hydrolysis of Al3+ was studied in aqueous 1 mol L−1 NaNO3 solution at different concentrations (20–200 mmol L−1) and temperatures (283.15–343.15 K) by potentiometry (ISE-H+, glass electrode). Many different speciation models were considered in the calculations and it was found that the best model is represented by the following species: Al(OH)2+, Al(OH)45+, Al13(OH)327+. Hydrolysis constants and enthalpy changes at different temperatures are reported.
Hydrolysis of methyltin(IV) trichloride in aqueous NaCl and NaNO3 solutions at different ionic strengths and temperatures
1999
The hydrolysis of methyltin(IV) trichloride (CH 3 SnCl 3 ) has been studied in aqueous NaCl and NaNO 3 solutions (0 < l/mol dm -3 ≤1), at different temperatures (15 ≤ T/°C ≤ 45) by potentiometric measurements (H + -glass electrode). By considering the generic hydrolytic reaction pCH 3 Sn 3+ + qH 2 O = (CH 3 Sn) p (OH) q 3p-q +qH + (logβ pq ), we have the formation of five species and logβ 12 = -3.36, logβ 13 = -8.99, logβ 14 = -20.27 and logβ 25 = -7.61. The first hydrolysis step is measurable only at very low pH values and was not determined: a rough estimate of the hydrolysis constant is logβ 11 = -1.5 (± 0.5). The dependence on ionic strength of logβ pq is quite different in NaNO 3 and N…
Novel acrylamido monomers with higher hydrophilicity and improved hydrolytic stability: II. Properties of N-acryloylaminopropanol
1996
The physico-chemical properties and the electrophoretic behavior of the novel set of monomers reported by (Simo-Alfonso et al., Electrophoresis 1996, 17, 723-731) have been evaluated. Of utmost importance was the combination of high hydrophilicity and extreme hydrolytic stability, most desired properties for, any electrophoretic matrix, especially for protein fractionation. One of these monomers (N-acryloylaminopropanol, AAP) was found indeed to be extremely hydrophilic (with a partition coefficient P of only 0.10, vs. P = 0.13 for N-acryloylaminoethoxyethanol and P = 0.20 for acrylamide) and to possess excellent stability to alkaline hydrolysis. Its hydrolysis constant (0.008 L mol-1 min-1…