ECEST interest in the use of ferrate compounds as strong ' oxidizing agents prompted an investigation of some factors influencing the stability of potassium ferrate solutions. In a study of the st,ahility of ferrate ions in aqueous solutions, Schreyer and Ockerman (2j found that the more dilute solutions of ferrate are more stable. They found also that some added salts, after increasing the initial deconiposition rate of ferrate solutions, apparently staliiljze the remainder; and that ferrate ions are more stable in buffer solutions of p H 8 than those of pH 7. These authors believe that the major factor influencing stability is the alkalinity of the solution. From qualitative experiments Schreyer ( 1 ) reported that solutions of potassium ferrate were partially decomposed photochemically over a period of 9.5 hours.Since it seemed desirable to establish the factors influencing the stability of ferrate compounds in connection with other xork, a quantitative study of t,he effects of light, temperature, alkalinity, and concentration, on the decomposition of aqueous solutions of potassium ferrate was made under carefully controlled conditions. PROCEDUREThe potassium ferrate was prepared by the method reported by Thompson, Ockerman, and Schreyer (4). To determine the effect of light on the decomposition rate of solutions of potassium ferrate under varying conditions, each of the experiments described below was performed using identical solutions in three flasks placed in a thermostat. One flask was exposed to the daylight in the laboratory, one was placed in the path of a beam of light from a 150-m-att G.E. spotlight, and one was painted black to exclude light. The latter was fitted with a rubber stopper containing a release valve to permit the escape of oxygen.As it was impossible to maintain a constant temperature with the splotlight shining directly on the bath, a 3000-ml. beaker of water was inserted between the bath and the spotlight to absorb most of the heat radiation. In this manner the temperature was successfully maintained constant to within +O.l O C.The solutions were analyzed by pipetting 10-ml. portions and determining the ferrate concentration by the chromite method ( 3 ) . Analyses were performed at varying intervals over a 2-hour period after the potassium ferrate solutions were prepared.Preliminary experiments indicated that several factors such as stirring, vibrations, and exposure of dry samples to the atmosphere influenced the decomposition. To minimize these factors the solutions were not stirred, and every effort was made to maintain constant conditions except for the one condition varied in 1 Present address, University of Cincinnati, Cincinnati, Ohio. rvlc each series of experiments. obtained.In this way reproducible rcwults were RESULTSEffect of Temperature. To study the effect of temperature on stability, quantitative determinations 15-ere made on aqueous solutions of potassium ferrate at' temperatures of 25' and 0.5' C. The results in Figure 1 shox that at 25" C. the concentration of potass...

Solubilities of 2,4-dihydroxybenzophenone have been measured at 298 K in 19 organic solvents. Combination with a known value of the solubility in water enables corresponding partition coefficients from water to these solvents to be deduced. It is shown that solubilities, via the partition coefficients, can yield the Abraham descriptors for 2,4-dihydroxybenzophenone, and that these, in turn, can be used to estimate a very large number of further solubilities, partition coefficients, and values of biological and environmental properties. This method of extracting information from solubilities is further illustrated using literature data on solubilities of biotin and of caprolactam.

Infinite dilution activity coefficients (γ∞) were measured at 298 K for 12 different aliphatic hydrocarbons (alkanes, cycloalkanes, alkenes), 11 different aromatic compounds (benzene, alkylbenzenes, halobenzenes, naphthalene), and 2-chloro-2-methylpropane dissolved in 2-butoxyethanol at 298 K using a headspace gas chromatographic method. As part of the experimental study solubilities of 19 crystalline nonelectrolyte solutes (2-hydroxybenzoic acid, acetylsalicylic acid, 3,5-dinitro-2-methylbenzoic acid, acenaphthene, trans-stilbene, xanthene, phenothiazine, 3,5-dinitrobenzoic acid, 3-chlorobenzoic acid, 2-methylbenzoic acid, 4-chloro-3-nitrobenzoic acid, 2-chloro-5-nitrobenzoic acid, benzoic acid, 4-aminobenzoic acid, benzil, thioxanthen-9-one, 3-nitrobenzoic acid, fluoranthene, and diphenyl sulfone) were determined in 2-butoxyethanol at 298 K using a static, spectrophotometric method. The experimental values 2 were converted to gas-to-2-butoxyethanol, water-to-2-butoxyethanol partition coefficients, and molar solubility ratios using standard thermodynamic relationships. Abraham model correlations for solute transfer into 2-butoxyethanol were derived from the calculated partition coefficients and solubility ratios. The derived Abraham model describes the observed partition coefficient and solubility data to within 0.14 log units (or less).

Infinite dilution activity coefficients (γ∞) were measured at 298 K for 13 different aliphatic hydrocarbons (alkanes, cycloalkanes, alkenes), 12 different aromatic compounds (benzene, alkylbenzenes, halobenzenes, naphthalene), and 2-chloro-2-methylpropane dissolved in 2-ethoxyethanol, along with solubilities for 11 crystalline organic compounds (xanthene, phenothiazine, acenaphthene, diphenyl sulfone, 3,5-dinitro-2-methylbenzoic acid, 3-chlorobenzoic acid, 2-methylbenzoic acid, 4-chloro-3-nitrobenzoic acid, 3,5-dinitrobenzoic acid, benzil, and thioxanthen-9-one) dissolved in 2-ethoxyethanol at 298 K. The experimental values were converted to gas-to-2-ethoxyethanol partition coefficients, water-to-2-ethoxyethanol partition coefficients, and molar solubility ratios using standard thermodynamic relationships.The calculated partition coefficient data and molar solubility ratios, combined with published literature values, were used to derive Abraham model correlations for solute transfer into 2-2 ethoxyethanol from both water and the gas phase. The derived Abraham model correlations predicted the observed values to within 0.15 log units (or less).

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