The activity coefficients of methyl acetate (MeOAc), ethyl acetate (EtOAc), n-propyl acetate (n-PrOAc), n-butyl acetate (n-BuOAc), and n-pentyl acetate (n-PeOAc) have been measured at 25 °C in concentrated aqueous solutions of electrolytes using the distribution technique. The salts used were LiCl, NaCl, KC1, CsCl, KF, KBr, NaNOg, and NaC104. In general, the results obtained are as might be expected. A mechanistic explanation is given of the trends observed and unexpected features in the data are explained with the aid of some assumptions regarding the nature of ionic hydration. The apparent molar volumes of MeOAc have also been determined over the full range of molalities for each of the salts used in the activity coefficient determinations. These measurements are then used in conjunction with thermodynamic data for the salt solutions (from the literature) to calculate the MeOAc activity coefficients according to the expanded McDevit and Long equations developed in an earlier publication. Similar, but less accurate calculations have also been done for the activity coefficients of the larger esters. In these cases, apparent molar volumes were determined only in water. The calculations are found to have mixed success.
The McDevit and Long theory of nonelectrolyte activity coefficients in aqueous salt solutions has previously been developed only in its limiting form. In this paper the theory is expanded to.a consideration of concentrated aqueous electrolyte solutions and is applied to the solutions of several nonpolar nonelectrolytes for which experimental data exist in the literature and for which a comparison can also be made with calculations based upon the statistical mechanical description of hard-sphere fluids. The alternate approaches are found to have similar success in prediction.trast to previous electrostatic treatments, Conway, Des-
A calorimeter has been
constructed and used to determine the limiting enthalpies of solution (ΔHS)
of a series of alkyl acetates (methyl, ethyl, propyl, butyl and t-butyl) in
water and aqueous solutions of some of the following salts: LiCl,
NaCl, KCl, CsCl, KF, KBr, NaNO3
and NaClO4. These measurements are combined with previous activity
coefficient determinations to obtain the thermodynamics of transfer for the
esters. In the case of transfer to NaCl solutions,
scaled-particle theory calculations are used to determine the thermodynamics of
cavity transfer, which, when combined with the experimental total-transfer
quantities, give rise to a set of quantities that we have called the
interaction transfer quantities. These quantities indicate that the predominant
factors in the transfer of neutral molecules containing both polar and
non-polar segments from water to NaCl solutions are
the transfer of the cavity and of the interactions of the polar group. The
interactions of the alkyl side chains are shown to be similar to those of
alkane molecules.
The fate of the hydrocarbon fragments in the phototarnishing of silver by several gaseous alkyl iodides (RI) is reported. The only gaseous product of reaction is the dimer alkane (R-R).Reaction rates depend linearly on light intensity, and the rate of alkane production was unaffected by the presence of a gaseous radical scavenger. The results obtained are consistent with a mechanism previously proposed for phototarnishing.
Unter Bedingungen, bei denen keine Gasphasenphotolyse der Alkyljodide (I) eintritt, reagieren diese mit Silber hauptsächlich unter Bildung der n‐Alkane (II).
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