Abstract

The reaction rate of the hydrolysis of fluorescein diacetate (FDA) is several times larger in the frozen state than that in the unfrozen solution of the same composition at the same temperature. The freeze concentration of reactants in the liquid phase expelled form ice crystals cannot explain the kinetic enhancement of pseudo first order reactions such as the FDA hydrolysis. However, the reaction rate increases as the freeze concentration ratio becomes larger at a constant temperature. Direct pH measurements have revealed that the basicity of the liquid phase is unchanged at any concentration ratio, suggesting that the reactivity enhancement is not caused by increased basicity. The reaction rate enhancement is clearly related to the size of the space in which the liquid phase is confined upon freezing. The ice wall itself or the water structure formed near the wall should thus be responsible for this kinetic enhancement.

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.