Abstract

Abstract1H spin‐echo NMR techniques were used to study the kinetics of proton exchange in the systems Be(NO3)2 in mixtures of water‐dimethyl sulfoxide(d6) and water‐acetone(d6) as a function of temperature, solvent composition and beryllium concentration. With increasing mole fraction of the organic component the total rate is reduced due to the decreasing contribution of protolysis of the hydrated beryllium(II) ion. Water exchange between coordinated sites at the beryllium(II) ion and the bulk solution dominates the proton exchange rate for DMSO mole fractions greater than 0.4 and for acetone mole fractions greater than 0.6, respectively. The calculated rates are almost independent of the solvent composition and beryllium concentration. Their values as well as the activation parameters are close to previous results on water exchange in the pure aqueous beryllium system using 17O NMR measurements [1]. For a 0.2 molal solution of beryllium(II) nitrate in water‐DMSO a temperature dependent water coordination number was found in the DMSO rich region which can be explained in terms of the extensive hydrogen bonded structure of the bulk solvent and of preferential solvation of beryllium(II) ions by water in these solutions.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.