The formation of nonvolatile products of the oxidation of a bromide ion during the interaction between gaseous ozone and powdered crystalline KBr is studied. It is found that potassium bromate KBrO3 is the main product of the reaction. The influence of major experimental factors (the duration of ozonation, the concentration of ozone, the humidity of the initial gas, and the temperature) on the rate of formation of bromate is studied. The effective constants of the formation of bromate during the interaction between O3 and Br– in a heterogeneous gas–solid body system and in a homogeneous aqueous solution are compared.

The value of the molar absorption coefficient of ozone in aqueous solutions (2992 ± 71 M–1 cm–1 at 260 nm) is found based on the determination of ozone concentration by iodometry. This value is confirmed by the results of determination of O3 concentration by reaction with the bromide ion and virtually coincides with the maximum absorption coefficient of ozone in the gas phase in the region the Hartley band. In the determinations of ozone concentration in aqueous solutions by direct spectrophotometry, we recommend the value of the molar absorption coefficient ε(О3)260 = 3000 M–1 cm–1.

A mechanism and kinetic model for the synthesis of peroxide radical condensate via the low-temperature interaction of hydrogen atoms with O2 molecules is proposed. The main components of the reaction, hydrogen tetroxide H2O4 and hydrogen peroxide H2O2, are formed in a low-temperature liquid layer formed near the cold surface during synthesis. Molecules of H2O4 and H2O2 are stabilized by transitioning to the solid phase. The dependences of the \(N_{O_2 } /N_{H_2 O_2 }\) ratio on the ratio of concentrations of H and O2 in the gas phase, calculated on the basis of the model, are consistent with the experimental data.

It is shown by means of direct spectrophotometry in the UV and visible ranges that the only product of the O3 reaction with Cl−(aq) in an acidic medium is molecular chlorine Cl2; in solutions, it is in equilibrium with the complex ion Cl 3 − . It is found that the consumption of one ozone molecule corresponds to the formation of one chlorine molecule. The stoichiometric equation for the reaction is obtained.

Relying on experimental data on products and the kinetic features of the complex reaction between O3 and Cl−(aq), we establish that the primary stage of the reaction proceeds via a mechanism in which an oxygen atom is transferred from an ozone molecule to a chloride ion. Analyzing the thermodynamic parameters of the primary stage, we conclude that a long-lived intermediate complex of a chloride ion and ozone is initially formed. The mechanism of acid catalysis in the reaction between O3 and Cl−(aq) is described as the formation of a protonated intermediate complex, HO3Cl, in the acidic medium and its rapid decomposition toward the formation of products.

It is found that chloride-ion oxidation by ozone via electron transfer mechanism does not occur due to its extremely high endoergicity and negligibly low rate. It is concluded that all processes supposedly associated with this reaction, particularly ozone decomposition in sodium chloride solution initiated by Cl· atoms, do not take place either. It is shown that experimental data on the products and kinetic regularities of the interaction of O3 with Cl− contradict the assumption that the electron transfer reaction is its primary stage. In fact, chloride-ion oxidation by ozone proceeds via the mechanism of oxygen atom transfer. It is noted that in order to estimate the possibility of using an ozonated physiological saline in medicine, the formation of chloride-ion oxidation products and ozonation byproducts must be taken into account.

One of the methods for the synthesis of peroxy-radical condensates is the condensation at liquid nitrogen temperature of an H2+O2 mixture dissociated in an electrical discharge at low pressure. Peroxy-radical condensates are thought to contain substantial quantities of higher hydrogen peroxides H2O3 and H2O4. The present work investigates the influence of experimental parameters on the synthesis of peroxy-radical condensates from an H2+O2 mixture, analyses the relevant literature, and recommends the optimal experimental conditions for the synthesis. The synthesis is carried out in a U-tube electrical discharge reactor (inner diameter ∼15 mm), immersed in liquid nitrogen, at rather low pressure (0.5–1 Torr). The maximum conversion of initial O2 into higher hydrogen peroxides was observed at a composition of initial gas mixture of 66.7% H2 + 33.3% O2.

Mathematical modeling of chemical reaction kinetics in the afterglow of electrical discharges in gas mixtures 66.7% H2 + 33.3% O2, 3% H2 + 97% O2, and 75% H2 + 25% CO2 and in vapors of H2O2 and H2O has been performed. The model included 50 chemical reactions for hydrogen-oxygen systems and 82 reactions for H2 + CO2 gas mixture. The reactions of heterogeneous loss of active particles were also included in the model. For every system investigated, a minimal set of significant chemical reactions was constructed sufficient for adequate description of experimental results. The concentration of particles not detected in experiment was estimated. The initial gas-phase particles were revealed for the synthesis of peroxy-radical condensates in hydrogen-oxygen systems and formic acid from the mixture H2 + CO2.

The solubility of ozone in pure water and aqueous solutions of sulfuric, phosphoric, and perchloric acids was determined at 20°C. An increase in the concentration of H 3 PO 4 and HClO 4 (to 14.8 and 9.5 M, respectively) caused a monotonic decrease in the solubility of ozone. The solubility of ozone in sulfuric acid was minimum at a 12 M concentration; the solubility then increased and, in 17.9 M H 2 SO 4 , reached almost the same value as in pure water. The ratio between the concentrations of O 3 in solution and the gas phase was 0.276 in pure water, 0.122 in 12 M H 2 SO 4 , and 0.265 in 17.9 M H 2 SO 4 . The results obtained are compared with the available literature data.