DOCSLIB.ORG

The Oxidation of Sulfur(IV) by Reaction with Iron(III): a Critical Review and Data Analysis Cite This: Phys

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
The Oxidation of Sulfur(IV) by Reaction with Iron(III): a Critical Review and Data Analysis Cite This: Phys PCCP View Article Online PAPER View Journal | View Issue The oxidation of sulfur(IV) by reaction with iron(III): a critical review and data analysis Cite this: Phys. Chem. Chem. Phys., 2018, 20,4020 Peter Warneck The dependences on ionic strength of the hydrolysis constants of Fe3+ and of the first dissociation constant of sulfurous acid are briefly reviewed. The data are needed to derive from apparent stability constants reported in the literature the stability constants for the three iron–sulfito complexes defined 2+ À + + À À + by the equilibria (c1) FeOH + HSO3 = FeSO3 +H2O, (c2) FeSO3 + HSO3 = Fe(SO3)2 +H , (c3a) À À 2À 3 À1 Fe(SO3)2 + HSO3 = Fe(SO3)3H , where Kc1 = 1982 Æ 518 dm mol , Kc2 = 0.72 Æ 0.08, Kc3a = 189 Æ 9dm3 molÀ1 (ionic strength m = 0.1 mol dmÀ3). The rapid formation of these complexes is followed by À a slower decomposition leading to the formation of SO3 radicals; the associated rate coefficients are À1 À1 À1 k1 =0.19s , k1a E 0.04 s ,andk1b E 0.08 s , respectively. The subsequent reaction leads to dithionate and sulfate as products. Overall rates and product yields from a variety of studies of the slow reaction Creative Commons Attribution 3.0 Unported Licence. are found to be consistent with a mechanism, in which the production of dithionate occurs mainly by the À + À 2+ 3+ reaction of SO3 with FeSO3 and that of sulfate by the reaction of SO3 with FeOH and/or Fe .Therole Received 9th November 2017, of copper as a catalyst is also analyzed. Rate coefficients for individual reactions are estimated from the data Accepted 9th January 2018 at low pH (m =1.0moldmÀ3) under conditions where the 1 : 1-complex is prevalent. They are extrapolated to DOI: 10.1039/c7cp07584g lower ionic strengths for an analysis of the data obtained at higher pH to explore conditions when reactions of the higher complexes become important. The overall rate and the product yields of the reaction depend rsc.li/pccp critically on the pH, the initial ratio of S(IV)toFe(III)andtheionicstrength of the solution. This article is licensed under a Introduction S(IV). Stopped flow spectrophotometry has been used to follow the formation and decay of the complexes.14–17 Measurements Iron belongs to a group of transition metals that are known to at short reaction times suggest the existence of three complexes 1 catalyze the oxidation of S(IV) in aqueous solution. Such resulting from the successive addition to Fe(III)ofS(IV)as Open Access Article. Published on 15 January 2018. Downloaded 9/29/2021 12:32:44 PM. 17,19,20 reactions are of interest especially in the atmospheric sciences ligand. Absorbance changes due to the variation of S(IV) because they are predicted to occur in the aqueous phase of concentrations have been exploited to derive apparent stability clouds and fogs, where they would contribute to the removal of constants for the complexes under various experimental 1–3 14,17–19 SO2 from the atmosphere. Thus, it is not surprising that the conditions. Unfortunately, the results have never been Fe(III)-catalyzed oxidation of S(IV) in aerated aqueous solutions has subjected to a detailed analysis, so that the true stability been studied in much detail.1 A consistent chemical mechanism constants are still not available. The slower subsequent reaction, 4,5 was developed, which incorporates a chain reaction carried by which leads to Fe(II), S(V)andS(VI) as products, has been studied sulfuroxy radicals, and rate coefficients are available for most of the by product analysis under conditions when the reaction is 6–8 9–14 individual reactions involved. But Fe(III) is known to oxidize S(IV) sufficiently slow. In reviewing these publications I have found also in the absence of oxygen. Far fewer studies have dealt with that the modification of a simple reaction mechanism first this process,9–16 and no consensus has been reached regarding proposed by Higginson and Marshall9 can explain most if not the relevant mechanism. This reaction in de-aerated solutions is all of the experimental results. the subject of the present critical analysis. Fundamental to an analysis of all experimental data is a There is agreement that the reaction is initiated by the knowledge of the speciation of Fe(III) and S(IV) resulting from 3+ formation of one or more iron–sulfito complexes. The presence the hydrolysis of Fe and SO2aq, respectively, and their depen- of such complexes is indicated by the appearance, and the dence on pH and ionic strength. This makes it necessary to subsequent fading, of a reddish brown color when a solution review briefly the hydrolysis constants of iron, and the first containing Fe(III) is mixed with another solution containing dissociation constant of sulfurous acid. Whereas the ionic strength dependences of the iron hydrolysis constants are quite Max-Planck Institute for Chemistry, Hahn-Meitner Weg 1, 55128 Mainz, Germany. well known, that of the dissociation constant of sulfurous acid E-mail: [email protected] appears to have not been well defined in the literature so that it 4020 | Phys. Chem. Chem. Phys., 2018, 20, 4020--4037 This journal is © the Owner Societies 2018 View Article Online Paper PCCP needs to be re-examined. Following these preliminaries spectrophotometric measurements – conducted mainly at 340 nm the data available for the apparent stability constants of the wavelength – and the solid line represents the best fit to the Fe(III)–S(IV) complexes are reviewed, the true stability constants extended Debye–Hu¨ckel equation are derived, and rate coefficients of their formation are discussed. 0 1 1 log K = log K À 2.04m2/(1 + 2.4m2) À 0.01m, (1) The results are then used in the subsequent analysis of the h1 h1 0 experimental data reported for the slower reaction, which where log Kh1 = À2.174 is obtained by extrapolation. The follows the decomposition of the complexes. In addition to numerical parameters in this equation were originally suggested making use of functional relationships in evaluating the experi- by Milburn and Vosburgh,21 whose measurements covered ionic mental data, computer simulations were carried out aiming to strengths up to m = 3.0. While spectrophotometry has been the reproduce the experimental data. favored measurement technique, potentiometric titration has also been applied, based on measuring simultaneously the hydrogen ion concentration and the Fe3+/Fe2+ redoxpotential.Bymeansof Iron(III) in aqueous solution computer-assisted analyses of the titration curves, Byrne et al.30 28 Trivalent iron, Fe3+, undergoes hydrolysis in aqueous solution and Stefanson have obtained results in perfect agreement with 2+ + 4+ 21 whereby FeOH , Fe(OH)2 , and Fe2(OH)2 are formed as those of Milburn and Vosburgh. products. The sum of all species and the total concentration Whereas the dependence on ionic strength of the first will be designated Fe(III) and [FeIII]tot, respectively. The relative hydrolysis constant is well documented, measurements of the concentrations of the different species are determined second hydrolysis constant are still sparse. The equilibrium by equilibria that depend on the pH, the ionic strength and may be written in two ways: the total concentration. In acidic solutions the solubility of 3+ + + Fe +2H2O = Fe(OH)2 +2H (h2) Fe(III) decreases with increasing pH; the final hydrolysis 2+ + + product Fe(OH)3 is the least soluble. Precipitation sets in at FeOH +H2O = Fe(OH)2 +H (h2a) Creative Commons Attribution 3.0 Unported Licence. pH 4 4, even at low concentrations, so that experimental + + 2 3+ studies of Fe(III) are restricted to the more acidic pH regime. Kh2 = [Fe(OH)2 ][H ] /[Fe ] At pH 2–3 the major species are Fe3+ and FeOH2+. The extent + + 2+ of dimer formation can be minimized by keeping [FeIII]tot Kh2a = [Fe(OH)2 ][H ]/[FeOH ] below 1 mmol dmÀ3. Under such conditions the dominant equilibrium is Both equilibrium constants are related in that Kh2a = K /K . The first expression is prevalent in the literature, 3+ 2+ + h2 h1 Fe +H2O = FeOH +H (h1) however. Early attempts to determine the equilibrium constant by means of potentiometric titration25,31,32 gave results that This article is licensed under a 2+ + 3+ 30 Kh1 = [FeOH ][H ]/[Fe ] scattered over a wide range. Then Byrne et al. critically reviewed the data and concluded that potentiometric titration The H2O molecule causing the hydrolysis is taken from the is not sufficiently sensitive and unsuitable for the determina- 3+ tion of K . On the other hand, more recent optical absorption Open Access Article. Published on 15 January 2018. Downloaded 9/29/2021 12:32:44 PM. hydration sphere of Fe . In the following, the hydration sphere h2 will be neglected, however. Fig. 1 shows Kh1 as a function studies over an extended range of pH have revealed a spectrum 28,33,34 + of ionic strength at 25 1C. Points are values obtained from that was assigned, to Fe(OH)2 . This made the determi- nation of Kh2 by means of spectrophotometry possible. Stefansson28 has summarized the available data and suggested an ionic strength dependence 0 1 1 log Kh2 = log Kh2 À 3.06m2/(1 + 1.58m2) (2) 0 where log Kh2 = À5.76 Æ 0.06 was again obtained by extrapola- tion. This value, as well as that in the denominator of the second term, is still uncertain because of an insufficient number of data available at low ionic strengths. 4+ The equilibrium constant of the Fe2(OH)2 complex may also be defined in two ways: 3+ 4+ + Fe +2H2O=Fe2(OH)2 +2H (h3) 2+ 2+ 4+ Fig.
Load more

Recommended publications
  • Enhanced Heterogeneous Uptake of Sulfur Dioxide on Mineral Particles Through Modification of Iron Speciation During Simulated Cloud Processing
    Atmos. Chem. Phys., 19, 12569–12585, 2019 https://doi.org/10.5194/acp-19-12569-2019 © Author(s) 2019. This work is distributed under the Creative Commons Attribution 4.0 License. Enhanced heterogeneous uptake of sulfur dioxide on mineral particles through modification of iron speciation during simulated cloud processing Zhenzhen Wang1, Tao Wang1, Hongbo Fu1,2,3, Liwu Zhang1, Mingjin Tang4, Christian George5, Vicki H. Grassian6, and Jianmin Chen1 1Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Institute of Atmospheric Sciences, Fudan University, Shanghai, 200433, China 2Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China 3Collaborative Innovation Center of Atmospheric Environment and Equipment Technology (CICAEET), Nanjing University of Information Science and Technology, Nanjing 210044, China 4State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China 5University of Lyon, Université Claude Bernard Lyon 1, CNRS, IRCELYON, 69626, Villeurbanne, France 6Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093, USA Correspondence: Hongbo Fu ([email protected]) and Jianmin Chen ([email protected]) Received: 7 May 2019 – Discussion started: 5 June 2019 Revised: 7 August 2019 – Accepted: 5 September 2019 – Published: 9 October
    [Show full text]
  • SO2 Removal by NH3 Gas Injection: Effects of Temperature and Moisture Content
    Ind. Eng. Chem. Res. 1994,33, 1231-1236 1231 SO2 Removal by NH3 Gas Injection: Effects of Temperature and Moisture Content Hsunling Bai' Institute of Environmental Engineering, National Chiao- Tung University, Hsin-Chu, Taiwan, R.O.C. Pratim Biswas and Tim C. Keener Department of Civil and Environmental Engineering, University of Cincinnati, Cincinnati, Ohio 45221 -0071 The removal of SO2 by NH3 gas injection at various temperatures and moisture contents has been studied experimentally. The product compositions of the NH3-SO2-HzO vapor reactions were also reported. A thermodynamic analysis was carried out to predict the SO2 removal as well as the product compositions. Both the experimental results and thermodynamic analysis indicated that SO2 removal and the product compositions are sensitive to the reaction temperature. Moisture content, once in large excess of the stoichiometric requirement, does not have a strong effect on the product compositions but plays an important role in the SO2 removal. Introduction conditions. Stromberger (1984) used X-ray diffraction and identified the product particles to be (NH&S04 Sulfur dioxide removal from flue gases is a goal of many crystals. air pollution engineers. Significant efforts in the develop- ment of new flue gas desulfurization (FGD) technologies Although a number of studies on the removal of SO2 are being made. Major processes related to FGD tech- from flue gases by NH3 injection have been conducted, nologies include water scrubbing, metal ion solutions, there is disagreement on the operating condition (such as catalytic oxidation, dry or semidry adsorption, wet lime temperature) that a high removal efficiency can be or limestone scrubbing, double alkali process, and ammonia obtained.
    [Show full text]
  • Focus on Sulfur Dioxide (SO2)
    The information presented here reflects EPA's modeling of the Clear Skies Act of 2002. The Agency is in the process of updating this information to reflect modifications included in the Clear Skies Act of 2003. The revised information will be posted on the Agency's Clear Skies Web site (www.epa.gov/clearskies) as soon as possible. Overview of the Human Health and Environmental Effects of Power Generation: Focus on Sulfur Dioxide (SO2), Nitrogen Oxides (NOX) and Mercury (Hg) June 2002 Contents The Clear Skies Initiative is intended to reduce the health and environmental impacts of power generation. This document briefly summarizes the health and environmental effects of power generation, specifically those associated with sulfur dioxide (SO2), nitrogen oxides (NOX), and mercury (Hg). This document does not address the specific impacts of the Clear Skies Initiative. • Overview -- Emissions and transport • Fine Particles • Ozone (Smog) • Visibility • Acid Rain • Nitrogen Deposition • Mercury Photo Credits: 1: USDA; EPA; EPA; VTWeb.com 2: NADP 6: EPA 7: ?? 10: EPA 2 Electric Power Generation: Major Source of Emissions 2000 Sulfur Dioxide 2000 Nitrogen Oxides 1999 Mercury Fuel Combustion- Industrial Processing electric utilities Transportation Other stationary combustion * Miscellaneous * Other stationary combustion includes residential and commercial sources. • Power generation continues to be an important source of these major pollutants. • Power generation contributes 63% of SO2, 22% of NOX, and 37% of man-made mercury to the environment. 3 Overview of SO2, NOX, and Mercury Emissions, Transport, and Transformation • When emitted into the atmosphere, sulfur dioxide, nitrogen oxides, and mercury undergo chemical reactions to form compounds that can travel long distances.
    [Show full text]
  • Section 2. Hazards Identification OSHA/HCS Status : This Material Is Considered Hazardous by the OSHA Hazard Communication Standard (29 CFR 1910.1200)
    SAFETY DATA SHEET Nonflammable Gas Mixture: Carbon Monoxide / Nitric Oxide / Nitrogen / Sulfur Dioxide Section 1. Identification GHS product identifier : Nonflammable Gas Mixture: Carbon Monoxide / Nitric Oxide / Nitrogen / Sulfur Dioxide Other means of : Not available. identification Product type : Gas. Product use : Synthetic/Analytical chemistry. SDS # : 012833 Supplier's details : Airgas USA, LLC and its affiliates 259 North Radnor-Chester Road Suite 100 Radnor, PA 19087-5283 1-610-687-5253 24-hour telephone : 1-866-734-3438 Section 2. Hazards identification OSHA/HCS status : This material is considered hazardous by the OSHA Hazard Communication Standard (29 CFR 1910.1200). Classification of the : GASES UNDER PRESSURE - Compressed gas substance or mixture EYE IRRITATION - Category 2A TOXIC TO REPRODUCTION - Category 1 GHS label elements Hazard pictograms : Signal word : Danger Hazard statements : Contains gas under pressure; may explode if heated. Causes serious eye irritation. May damage fertility or the unborn child. May displace oxygen and cause rapid suffocation. Precautionary statements General : Read and follow all Safety Data Sheets (SDS’S) before use. Read label before use. Keep out of reach of children. If medical advice is needed, have product container or label at hand. Close valve after each use and when empty. Use equipment rated for cylinder pressure. Do not open valve until connected to equipment prepared for use. Use a back flow preventative device in the piping. Use only equipment of compatible materials of construction. Prevention : Obtain special instructions before use. Wear protective gloves. Wear protective clothing. Wear eye or face protection. Wash thoroughly after handling. Response : IF exposed or concerned: Get medical advice or attention.
    [Show full text]
  • SDS # : 014869 Supplier's Details : Airgas USA, LLC and Its Affiliates 259 North Radnor-Chester Road Suite 100 Radnor, PA 19087-5283 1-610-687-5253
    SAFETY DATA SHEET Nonflammable Gas Mixture: Nitric Oxide / Nitrogen / Sulfur Dioxide Section 1. Identification GHS product identifier : Nonflammable Gas Mixture: Nitric Oxide / Nitrogen / Sulfur Dioxide Other means of : Not available. identification Product type : Gas. Product use : Synthetic/Analytical chemistry. SDS # : 014869 Supplier's details : Airgas USA, LLC and its affiliates 259 North Radnor-Chester Road Suite 100 Radnor, PA 19087-5283 1-610-687-5253 24-hour telephone : 1-866-734-3438 Section 2. Hazards identification OSHA/HCS status : This material is considered hazardous by the OSHA Hazard Communication Standard (29 CFR 1910.1200). Classification of the : GASES UNDER PRESSURE - Compressed gas substance or mixture GHS label elements Hazard pictograms : Signal word : Warning Hazard statements : Contains gas under pressure; may explode if heated. May displace oxygen and cause rapid suffocation. Precautionary statements General : Read and follow all Safety Data Sheets (SDS’S) before use. Read label before use. Keep out of reach of children. If medical advice is needed, have product container or label at hand. Close valve after each use and when empty. Use equipment rated for cylinder pressure. Do not open valve until connected to equipment prepared for use. Use a back flow preventative device in the piping. Use only equipment of compatible materials of construction. Prevention : Not applicable. Response : Not applicable. Storage : Protect from sunlight. Store in a well-ventilated place. Disposal : Not applicable. Hazards not otherwise : In addition to any other important health or physical hazards, this product may displace classified oxygen and cause rapid suffocation. Section 3. Composition/information on ingredients Substance/mixture : Mixture Other means of : Not available.
    [Show full text]
  • Recent Developments in Chalcogen Chemistry
    RECENT DEVELOPMENTS IN CHALCOGEN CHEMISTRY Tristram Chivers Department of Chemistry, University of Calgary, Calgary, Alberta, Canada WHERE IS CALGARY? Lecture 1: Background / Introduction Outline • Chalcogens (O, S, Se, Te, Po) • Elemental Forms: Allotropes • Uses • Trends in Atomic Properties • Spin-active Nuclei; NMR Spectra • Halides as Reagents • Cation Formation and Stabilisation • Anions: Structures • Solutions of Chalcogens in Ionic Liquids • Oxides and Imides: Multiple Bonding 3 Elemental Forms: Sulfur Allotropes Sulfur S6 S7 S8 S10 S12 S20 4 Elemental Forms: Selenium and Tellurium Allotropes Selenium • Grey form - thermodynamically stable: helical structure cf. plastic sulfur. R. Keller, et al., Phys. Rev. B. 1977, 4404. • Red form - cyclic Cyclo-Se8 (cyclo-Se7 and -Se6 also known). Tellurium • Silvery-white, metallic lustre; helical structure, cf. grey Se. • Cyclic allotropes only known entrapped in solid-state structures e.g. Ru(Ten)Cl3 (n = 6, 8, 9) M. Ruck, Chem. Eur. J. 2011, 17, 6382 5 Uses – Sulfur Sulfur : Occurs naturally in underground deposits. • Recovered by Frasch process (superheated water). • H2S in sour gas (> 70%): Recovered by Klaus process: Klaus Process: 2 H S + SO 3/8 S + 2 H O 2 2 8 2 • Primary industrial use (70 %): H2SO4 in phosphate fertilizers 6 Uses – Selenium and Tellurium Selenium and Tellurium : Recovered during the refining of copper sulfide ores Selenium: • Photoreceptive properties – used in photocopiers (As2Se3) • Imparts red color in glasses Tellurium: • As an alloy with Cu, Fe, Pb and to harden
    [Show full text]
  • Elemental Sulfur Aerosol-Forming Mechanism
    Elemental sulfur aerosol-forming mechanism Manoj Kumara and Joseph S. Franciscoa,1 aDepartment of Chemistry, University of Nebraska-Lincoln, Lincoln, NE 68588 Contributed by Joseph S. Francisco, December 21, 2016 (sent for review November 13, 2016; reviewed by James Lyons and Hua-Gen Yu) Elemental sulfur aerosols are ubiquitous in the atmospheres of Venus, reaction mechanism that may possibly convert the SOn + nH2S ancient Earth, and Mars. There is now an evolving body of evidence (n = 1, 2, 3) chemistries into the S8 aerosol in the gas phase suggesting that these aerosols have also played a role in the evolution (Scheme S1). It is the thermodynamics of these processes, and of early life on Earth. However, the exact details of their formation their catalysis by water and sulfuric acid, that we investigate here. mechanism remain an open question. The present theoretical calcula- This mechanism may not only help in better understanding the tions suggest a chemical mechanism that takes advantage of the in- role of sulfur cycle involving SOn,S8, and H2S as the potential S n = teraction between sulfur oxides, SOn ( 1, 2, 3) and hydrogen sulfide MIF carrier from the atmosphere to the ocean surface, but may 0 (nH2S), resulting in the efficient formation of a Sn+1 particle. Interest- also provide deeper insight into the formation mechanism of S + → + ingly, the SOn nH2S Sn+1 nH2O reactions occur via low-energy aerosols in various other environments. pathways under water or sulfuric acid catalysis. Once the S + particles n 1 We first explored the uncatalyzed gas-phase reactions of SOn with are formed, they may further nucleate to form larger polysulfur aero- nH2S using quantum-chemical calculations at the coupled cluster sols, thus providing a chemical framework for understanding the for- single and double substitution method with a perturbative treatment 0 mation mechanism of S aerosols in different environments.
    [Show full text]
  • The Chemical and Preservative Properties of Sulfur Dioxide Solution for Brining Fruit
    The Chemical and Preservative Properties of Sulfur Dioxide Solution for Brining Fruit Circular of Information 629 June 1969 Agricultural Experiment Station, Oregon State University, Corvallis The Chemical and Preservative Properties of Sulfur Dioxide Solution for Brining Fruit C. H. PAYNE, D. V. BEAVERS, and R. F. CAIN Department of Food Science and Technology Sweet cherries and other fruits are preserved in sul- control are given in papers by Waiters et al. (1963) and fur dioxide solutions for manufacture into maraschino, Yang et al. (1966). cocktail, and glace fruit. The sulfur dioxide solution, Sulfur dioxide and calcium are directly related to commonly called brine, may be prepared from liquid brined cherry quality. Improper use of these chemicals sulfur dioxide, sodium bisulfite, or sodium metabisulfite may result in cherries that are soft, poorly bleached, or using alkali or acid to control pH. Calcium salts such as spoiled due to fermentation. It is the purpose of this calcium hydroxide, calcium carbonate, and calcium chlo- circular to show how the basic chemical and preservative ride are added to the brine to prevent cracking and pro- components of brine solutions are afifected during prep- mote firming of the fruit tissue through interaction with aration, storage, and use. pectic materials. Directions for brine preparation and Chemical Properties of Sulfur Dioxide Solutions When sulfur dioxide or materials containing sulfur range of sulfur dioxide concentrations, the relative dis- dioxide (bisulfite or metabisulfite) are dissolved in tribution of the sulfur dioxide ionic forms is constant. water, three types of chemical substances are formed: Within the initial pH range used for brining cher- sulfurous acid (H2SO3),1 bisulfite (HSO3"), and sulfite ries, there is a predominance of calcium bisulfite (SO~).
    [Show full text]
  • Section 2. Hazards Identification OSHA/HCS Status : This Material Is Considered Hazardous by the OSHA Hazard Communication Standard (29 CFR 1910.1200)
    SAFETY DATA SHEET Nonflammable Gas Mixture: Carbon Dioxide / Carbon Monoxide / Nitric Oxide / Nitrogen / Propane / Sulfur Dioxide Section 1. Identification GHS product identifier : Nonflammable Gas Mixture: Carbon Dioxide / Carbon Monoxide / Nitric Oxide / Nitrogen / Propane / Sulfur Dioxide Other means of : Not available. identification Product type : Gas. Product use : Synthetic/Analytical chemistry. SDS # : 019536 Supplier's details : Airgas USA, LLC and its affiliates 259 North Radnor-Chester Road Suite 100 Radnor, PA 19087-5283 1-610-687-5253 24-hour telephone : 1-866-734-3438 Section 2. Hazards identification OSHA/HCS status : This material is considered hazardous by the OSHA Hazard Communication Standard (29 CFR 1910.1200). Classification of the : GASES UNDER PRESSURE - Compressed gas substance or mixture GHS label elements Hazard pictograms : Signal word : Warning Hazard statements : Contains gas under pressure; may explode if heated. May displace oxygen and cause rapid suffocation. May increase respiration and heart rate. Precautionary statements General : Read and follow all Safety Data Sheets (SDS’S) before use. Read label before use. Keep out of reach of children. If medical advice is needed, have product container or label at hand. Close valve after each use and when empty. Use equipment rated for cylinder pressure. Do not open valve until connected to equipment prepared for use. Use a back flow preventative device in the piping. Use only equipment of compatible materials of construction. Prevention : Not applicable. Response : Not applicable. Storage : Protect from sunlight. Store in a well-ventilated place. Disposal : Not applicable. Hazards not otherwise : In addition to any other important health or physical hazards, this product may displace classified oxygen and cause rapid suffocation.
    [Show full text]
  • Electronic Structure, Stability, and Cooperativity of Chalcogen Bonding in Sulfur Dioxide and Hydrated Sulfur Dioxide Clusters
    Electronic structure, stability, and cooperativity of chalcogen bonding in sulfur dioxide and hydrated sulfur dioxide clusters: a DFT study and wave functional analysis Venkataramanan Natarajan Sathiyamoorthy ( [email protected] ) SHARP Substratum https://orcid.org/0000-0001-6228-0894 Research Article Keywords: Chalcogen bond, Hydrogen bond, Non-covalent interactions, QTAIM, Cooperativity Posted Date: July 7th, 2021 DOI: https://doi.org/10.21203/rs.3.rs-665149/v1 License: This work is licensed under a Creative Commons Attribution 4.0 International License. Read Full License Page 1/28 Abstract Density functional theory calculations and wave functional analysis are used to examine the (SO2)n and (SO2)n–H2O clusters with n = 1–7. The nature of interactions is explored by molecular electrostatic potentials, electron density distribution, atoms in molecules, noncovalent interaction, and energy decomposition analysis. The putative global minimum of SO2 molecules has a 3D growth pattern with tetrahedral. In the hydrated SO2 clusters, the pure hydrogen bond isomers are less stable than the O···S chalcogen bond isomers. The cluster absorption energy of SO2 on water increases with the size of sulfur dioxide, implying reactivity of sulfur dioxide with water increases with size. The presence of cooperativity was evident from the excellent linearity plot of binding energy/polarizability vs the number of SO2 molecules. Molecular electrostatic potential analysis elucidates the reason for the facile formation of S···O chalcogen than hydrogen bonding in hydrated sulfur dioxide. Atoms in molecule analysis characterize the bonds chalcogen and H bonds to be weak and electrostatic dominant. EDA analysis shows electrostatic interaction is dominated in complexes with more intermolecular chalcogen bonding and orbital interaction for systems with intermolecular H-bonding.
    [Show full text]
  • CHEMISTRY 1A NOMENCLATURE WORKSHEET Chemical Formula
    CHEMISTRY 1A NOMENCLATURE WORKSHEET Chemical Formula Nomenclature Practice: Complete these in lab and on your own time for practice. You should complete this by Sunday. Use the stock form for the transition metals. Give the formula for the following: 1. sulfur dioxide ____SO2______________ 26. methane ____CH4_____________ 2. sodium thiosulfate ____Na2S2O3__________ 27. copper (II) sulfate ____CuSO4___________ 3. ammonium phosphate ____(NH4)3PO4_________ 28. nitrogen dioxide ____NO2_____________ 4. potassium chlorate ____KClO3____________ 29. mercury (II) chloride ____HgCl2____________ 5. lithium hydroxide ____LiOH_____________ 30. tin (II) bromide ____SnBr2____________ 6. zinc nitrite ____Zn(NO2)2__________ 31. silver iodide ____AgI______________ 7. sodium sulfate ____Na2SO4____________ 32. magnesium bisulfite ____Mg(HSO3)2________ 8. cobalt (IV) bisulfite ____Co(HSO3)4_________ 33. carbon disulfide ____CS2______________ 9. cadmium nitrate ____Cd(NO3)2__________ 34. beryllium periodate ____Be(IO4)2__________ 10. nitric oxide ____NO_______________ 35. platinum (IV) cyanide ____Pt(CN)4___________ 11. hydrogen peroxide ____H2O2______________ 36. ammonia ____NH3______________ 12. carbon monoxide ____CO_______________ 37. dinitrogen oxide ____N2O______________ 13. silicon dioxide ____SiO2______________ 38. ferric oxide ____Fe2O3____________ 14. copper (I) bromide ____CuBr______________ 39. gold (III) chloride ____AuCl3____________ 15. iron (II) chromate ____FeCrO4____________ 40. strontium sulfide ____SrS______________ 16. mercury (I) fluoride
    [Show full text]
  • Sulfur Dioxide
    Sulfur Dioxide Crops 1 2 Identification of Petitioned Substance 3 4 Chemical Names: 15 CAS Numbers: 5 Sulfur dioxide 16 7446-09-5 6 17 7 Other Name: 18 Other Codes: 8 Sulfur (IV) oxide 19 EINECS 231-195-2 9 Sulfur superoxide 20 U.S. EPA Pesticide Chemical Code 077601 10 Sulfurous acid anhydride 21 CA DPR Chemical Code 561 11 Sulfurous anhydride 22 UN 1079 12 13 Trade Names: 14 Sulfurous oxide 23 24 Characterization of Petitioned Substance 25 26 Composition of the Substance: 27 28 Sulfur dioxide (SO2) is an angular molecule containing a sulfur atom and two oxygen atoms and can be produced 29 naturally or as a result of combustion of sulfur-containing substances such as petroleum or coal. The sulfur atom 30 has a formal charge of 0 and an oxidation state of +4 and is surrounded by 5 electron pairs. The chemical 31 structure of sulfur dioxide is shown below: 32 33 34 35 Properties of the Substance: 36 37 Sulfur dioxide is a colorless gas with a strong, pungent odor. It is nonflammable and very soluble in water. 38 Sulfur dioxide is a strong reducing agent and is highly reactive. 39 40 Due to its high vapor pressure, sulfur dioxide is primarily present in the gaseous phase and can move 41 unchanged to other natural surfaces, including water, soil, and vegetation, following release to the 42 atmosphere (ATSDR, 1998). Because of the high water solubility of sulfur dioxide, oceans can serve as sink 43 (ATSDR, 1998). Sulfur dioxide can be absorbed by soil if pH and moisture content are suitable (ATSDR, 44 1998).
    [Show full text]