Proton transfer in aqueous solutions

Table 10. Equilibrium Constants for Proton Transfers in Aqueous Solution...

If any equilibrium constants show this linearity, this behavior is most likely to be found among proton transfers of type (118) and type (120). The expressions for log K given in Table 11 show this linearity they represent, within the experimental error, the accurate data obtained by measurements on three proton transfers in aqueous solution. All three are of the type (120). 

The products of proton transfer in aqueous solution may also react with water. For example, the CIST ion produced when HCN loses a proton to water can accept a proton from a water molecule and form HCN again. Therefore, according to the Bronsted definition, CN is a base it is called the conjugate base of the acid HCN. In general, a conjugate base of an acid is the species left when the acid donates a proton ... 

When this probability is equal to 1 (uniform concentration), the reaction is of pseudo-first order. This is the case, for example, in photoinduced proton transfer in aqueous solutions from an excited acid M (=AH ) (see Section 4.5) M is always within the encounter distance with a water molecule acting as a proton acceptor, and thus proton transfer occurs effectively according to a unimolecular process. This is also the case of photoinduced electron transfer in aniline or its derivatives as solvents an excited acceptor is always in the vicinity of an aniline molecule as an electron donor. In both cases, the excited-state reaction occurs under non-diffusive conditions and is of pseudo-first order. 

This enzyme [EC 4.2.1.1], also referred to as carbonate dehydratase, is a zinc-dependent enzyme that catalyzes the reaction of carbon dioxide with water to form carbonic acid (or, of bicarbonate and a proton). See also Proton Transfer in Aqueous Solution Manometric Assay Methods Marcus Rate Theory... 

A Bronstcd-I.owry aeid is defined as a proton donor, a Bronsted-Loory base as a proton acceptor. The definitions apply generally toprotic systems those in which proton transfers can occur. A general equation expressing proton transfer in aqueous solution is ... 

A detailed mechanism (109) has been proposed for proton transfer in aqueous solution [59], viz. 

Electrochemical irreversibility caused by slow heterogeneous electron-transfer kinetics at the electrode surface can limit the ability of the measurement to yield thermodynamically meaningful potentials. While proton transfer in aqueous solutions is generally very fast, heterogeneous... 

While the above equation is the most accurate way to write the proton transfer in aqueous solution, we will simplify the equation to showjust the proton and formation of the new covalent bond. 

ULTRASONIC RELAXATION STUDIES OF THE KINETICS OF STACKING, CONFORMATIONAL TRANSITIONS AND PROTON TRANSFERS IN AQUEOUS SOLUTIONS OF MOLECULES AND MACROMOLECULES OF BIOLOGICAL INTEREST... 

For the study of proton transfers in aqueous solution it is vital to know about the fractionation on L30 and LO when they are involved as reactants. 

Proton Transfer in Aqueous Solution Exploring the Boundaries of Adaptive QM/MM... 

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