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Journal ArticleDOI

Aqueous oxidation of sulfur dioxide by hydrogen peroxide at low pH

01 Jan 1981-Atmospheric Environment (Elsevier)-Vol. 15, Iss: 9, pp 1615-1621
TL;DR: In this article, the rate of formation of oxidized sulfur is given by: d(S VI d t = (8±2) × 10 4 (H 2 O 2 )(SO 2.aq ) 0.1+(H + ) mole l −1 s −1
About: This article is published in Atmospheric Environment.The article was published on 1981-01-01. It has received 325 citations till now. The article focuses on the topics: Hydrogen peroxide & Sulfur.
Citations
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Journal ArticleDOI
Rolf Sander1
TL;DR: According to Henry's law, the equilibrium ratio between the abundances in the gas phase and in the aqueous phase is constant for a dilute solution as discussed by the authors, and a compilation of 17 350 values of Henry's Law constants for 4632 species, collected from 689 references is available at http://wwwhenrys-law.org
Abstract: Many atmospheric chemicals occur in the gas phase as well as in liquid cloud droplets and aerosol particles Therefore, it is necessary to understand the distribution between the phases According to Henry's law, the equilibrium ratio between the abundances in the gas phase and in the aqueous phase is constant for a dilute solution Henry's law constants of trace gases of potential importance in environmental chemistry have been collected and converted into a uniform format The compilation contains 17 350 values of Henry's law constants for 4632 species, collected from 689 references It is also available at http://wwwhenrys-laworg

1,935 citations

Journal ArticleDOI
TL;DR: In this paper, the authors identify specific compounds that are likely to contribute to the water-soluble fraction by juxtaposing observations regarding the extraction characteristics and the molecular composition of atmospheric particulate organics with compound-specific solubility and condensibility for a wide variety of organics.
Abstract: Although organic compounds typically constitute a substantial fraction of the fine particulate matter (PM) in the atmosphere, their molecular composition remains poorly characterized. This is largely because atmospheric particles contain a myriad of diverse organic compounds, not all of which extract in a single solvent or elute through a gas chromatograph; therefore, a substantial portion typically remains unanalyzed. Most often the chemical analysis is performed on a fraction that extracts in organic solvents such as benzene, ether or hexane; consequently, information on the molecular composition of the water-soluble fraction is particularly sparse and incomplete. This paper investigates theoretically the characteristics of the water-soluble fraction by splicing together various strands of information from the literature. We identify specific compounds that are likely to contribute to the water-soluble fraction by juxtaposing observations regarding the extraction characteristics and the molecular composition of atmospheric particulate organics with compound-specific solubility and condensibility for a wide variety of organics. The results show that water-soluble organics, which constitute a substantial fraction of the total organic mass, include C2 to C7 multifunctional compounds (e.g., diacids, polyols, amino acids). The importance of diacids is already recognized; our results provide an impetus for new experiments to establish the atmospheric concentrations and sources of polyols, amino acids and other oxygenated multifunctional compounds.

1,115 citations

Journal ArticleDOI
TL;DR: The Meteorological Synthesizing Centre-West (MSC-W) of the European Monitoring and Evaluation Programme (EMEP) has been performing model calculations in support of the Convention on Long Range Transboundary Air Pollution (CLRTAP) for more than 30 years as mentioned in this paper.
Abstract: The Meteorological Synthesizing Centre-West (MSC-W) of the European Monitoring and Evaluation Programme (EMEP) has been performing model calculations in support of the Convention on Long Range Transboundary Air Pollution (CLRTAP) for more than 30 years The EMEP MSC-W chemical transport model is still one of the key tools within European air pollution policy assessments Traditionally, the model has covered all of Europe with a resolution of about 50 km x 50 km, and extending vertically from ground level to the tropopause (100 hPa) The model has changed extensively over the last ten years, however, with flexible processing of chemical schemes, meteorological inputs, and with nesting capability: the code is now applied on scales ranging from local (ca 5 km grid size) to global (with 1 degree resolution) The model is used to simulate photo-oxidants and both inorganic and organic aerosols In 2008 the EMEP model was released for the first time as public domain code, along with all required input data for model runs for one year The second release of the EMEP MSC-W model became available in mid 2011, and a new release is targeted for summer 2012 This publication is in-tended to document this third release of the EMEP MSC-W model The model formulations are given, along with details of input data-sets which are used, and a brief background on some of the choices made in the formulation is presented The model code itself is available at wwwemepint, along with the data required to run for a full year over Europe

587 citations

Book ChapterDOI
01 Jan 1986
TL;DR: In this article, a graphical method is described whereby it may be ascertained whether a given reaction is controlled solely by reagent solubility and intrinsic chemical kinetic or is mass-transport limited by one or another of the above processes.
Abstract: Reactions of gases in liquid-water clouds are potentially important in the transformation of atmospheric pollutants affecting their transport in the atmosphere and subsequent removal and deposition to the surface. Such processes consist of the following sequence of steps: Mass-transport of the reagent gas or gases to the air-water interface; transfer across the interface and establishment of solubility equilibria locally at the interface; mass-transport of the dissolved gas or gases within the aqueous phase; aqueous-phase chemical reaction(s); mass-transport of reaction product(s) and possible subsequent evolution into the gas-phase. Description of the rate of the overall process requires identification of the rate-limiting step (or steps) and evaluation of the rate of such step(s). Identification of the rate-limiting step may be achieved by evaluation and comparison of the characteristic times pertinent to the several processes and may be readily carried out by methods outlined herein, for known or assumed reagent concentrations, drop size, and fundamental constants as follows: gas- and aqueous-phase diffusion coefficients; Henry’s law coefficient and other pertinent equilibrium constants; interfacial mass-transfer accommodation coefficient; aqueous-phase reaction rate constants(s). A graphical method is described whereby it may be ascertained whether a given reaction is controlled solely by reagent solubility and intrinsic chemical kinetic or is mass-transport limited by one or another of the above processes. In the absence of mass-transport limitation, reaction rates may be evaluated uniformly for the entire liquid-water content of the cloud using equilibrium reagent concentrations. In contrast, where appreciable mass-transport limitation is indicated, evaluation of the overall rate requires knowledge of and integration over the drop-size distribution characterizing the cloud.

504 citations

Journal ArticleDOI
TL;DR: In this article, a review of the current understanding of the chemical mechanisms leading to the generation of secondary pollutants in the troposphere is provided, with particular emphasis on chemical processes occurring in the planetary boundary layer.

490 citations

References
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Book
01 Jan 1999
TL;DR: Cotton and Wilkinson's Advanced Inorganic Chemistry (AIC) as discussed by the authors is one of the most widely used inorganic chemistry books and has been used for more than a quarter century.
Abstract: For more than a quarter century, Cotton and Wilkinson's Advanced Inorganic Chemistry has been the source that students and professional chemists have turned to for the background needed to understand current research literature in inorganic chemistry and aspects of organometallic chemistry. Like its predecessors, this updated Sixth Edition is organized around the periodic table of elements and provides a systematic treatment of the chemistry of all chemical elements and their compounds. It incorporates important recent developments with an emphasis on advances in the interpretation of structure, bonding, and reactivity.From the reviews of the Fifth Edition:* "The first place to go when seeking general information about the chemistry of a particular element, especially when up-to-date, authoritative information is desired." -Journal of the American Chemical Society.* "Every student with a serious interest in inorganic chemistry should have [this book]." -Journal of Chemical Education.* "A mine of information . . . an invaluable guide." -Nature.* "The standard by which all other inorganic chemistry books are judged."-Nouveau Journal de Chimie.* "A masterly overview of the chemistry of the elements."-The Times of London Higher Education Supplement.* "A bonanza of information on important results and developments which could otherwise easily be overlooked in the general deluge of publications." -Angewandte Chemie.

12,231 citations

Book
01 Jan 1952
TL;DR: The Selected Values of Chemical Thermodynamic Properties as mentioned in this paper, published by the National Bureau of Standards (NBS) in 1952, is a seminal work in the field of thermodynamics.
Abstract: The theoretical framework of thermodynamics was well established by the time NBS was founded, and certain important applications, such as improving the efficiency of steam engines, had been demonstrated. However, the broad application of thermodynamics to the design and control of industrial processes had to await the accumulation and organization of a large amount of experimental data, as well as theoretical contributions from quantum mechanics and statistical mechanics. The appearance of Selected Values of Chemical Thermodynamic Properties [1] in 1952 marked a significant milestone in this process. This book represented the culmination of 20 years of work by Frederick D. Rossini and coworkers in evaluating and systematizing the data that had appeared in the world literature on thermochemistry. It tabulated accurate values of the thermodynamic properties of all inorganic and simple organic compounds that had been investigated in a format that allowed prediction of the outcome of many thousands of chemical reactions. Such calculations, which indicate whether a reaction will take place and, if so, the extent of reaction and amount of heat released or absorbed, are immensely important in research and engineering. Selected Values, which was often referred to simply as “Circular 500” after its NBS publication designation, presented recommended values of the enthalpy (heat) of formation, Gibbs energy of formation, entropy, and heat capacity of individual chemical compounds in different physical states (solid, liquid, gas, or aqueous solution). All values were reduced to standard state conditions, defined by parameters such as temperature (25 C) and pressure (one standard atmosphere). Since the laws of thermodynamics require that the change in properties such as energy and entropy cannot depend on the path followed in going from an initial to a final state—otherwise one could build a perpetual motion machine—the net change in thermodynamic properties in a chemical reaction can be calculated by addition and subtraction of the standard state values for the substances taking part in the reaction. This allows a simple prediction of whether the reaction will occur at all and, if it does, whether it will go to completion. In intermediate situations, one can obtain a quantitative measure of the extent of reaction from the equilibrium constant, which is easily calculated from the tabulated standard state values. Finally, most chemical changes involve either an absorption or release of heat, and the amount of this heat may be calculated from the same data. Thus Selected Values provided an extremely powerful tool for predicting the course of chemical reactions, a goal of chemists since the earliest days of the science. The book itself was 822 pages in length and covered about 5000 chemical species. It was divided into two parts, the first dealing with the thermodynamic properties in a particular physical state and the second with the change in properties in transitions between states (such as melting and vaporization). All data were internally consistent, in the sense that all physical and thermodynamic relations existing between different properties for the same substance, or the same property for different substances, were satisfied by the tabulated values. The table layout in Circular 500 became the norm for thermodynamic tabulations throughout the world. Fig. 1. Frederick D. Rossini.

1,460 citations

Journal ArticleDOI
TL;DR: In this paper, the authors used the experimental data to calculate the rate of sulphate formation in water droplets under atmospheric conditions for each of the three oxidants, i.e., ozone, ozone and hydrogen peroxide.

330 citations

Journal ArticleDOI
TL;DR: In this article, an evaluation of the existing kinetic data related to the elementary, homogeneous reactions of SO 2 within the troposphere is made, and a set of preferred values of the rate constants for these reactions is presented.

252 citations

Journal ArticleDOI
TL;DR: In this article, the authors investigated the kinetics of sulfite by hydrogen peroxide over the pH range 4-8 and showed that the reaction probably proceeds via a nucleophilic displacement by H 2O_2 on HSO_3^- to form a peroxomonosulfurous acid intermediate which then undergoes a rate-determining rearrangement.
Abstract: The kinetics of the oxidation of sulfite by hydrogen peroxide has been investigated by stopped-flow spectrophotometry over the pH range 4-8. The rate law for the oxidation of sulfite in this pH range is -d[SO_2]_T/dt = k [H^+][H_2O_2][SO_2]_T([H^+]/([H^+] K_a_2)} + k'[HA][H_2O_2][SO_2]_T{[H^+]/([H^+] + K_a_2 where HA represents all possible proton donors in solution. The reaction probably proceeds via a nucleophilic displacement by H_2O_2 on HSO_3^- to form a peroxomonosulfurous acid intermediate which then undergoes a rate-determining rearrangement.

176 citations