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Naming Molecular Compounds General Instructions: Please Do the Activities for Each Day As Indicated
Teacher Name: Dwight Lillie Student Name: ________________________ Class: ELL Chemistry Period: Per 4 Assignment: Assignment week 2 Due: Friday, 5/8 Naming Molecular Compounds General Instructions: Please do the activities for each day as indicated. Any additional paper needed please attach. Submitted Work: 1) Completed packet. Questions: Please send email to your instructor and/or attend published virtual office hours. Schedule: Date Activity Monday (4/27) Read Sections 9.3, 9.5 in your textbook. Tuesday (4/28) Read and work through questions 1-9 Wednesday (4/29) Read and work through questions 10-14 Thursday (4/30) Read and work through questions 14-18 Friday (5/31) Read and work through questions 19-21 How are the chemical formula and name of a molecular compound related? Why? When you began chemistry class this year, you probably already knew that the chemical formula for carbon dioxide was CO2. Today you will find out why CO2 is named that way. Naming chemical compounds correctly is of paramount importance. The slight difference between the names carbon monoxide (CO, a poisonous, deadly gas) and carbon dioxide (CO2, a greenhouse gas that we exhale when we breathe out) can be the difference between life and death! In this activity you will learn the naming system for molecular compounds. Model 1 – Molecular Compounds Molecular Number of Atoms Number of Atoms in Name of Compound Formula of First Element Second Element ClF Chlorine monofluoride ClF5 1 5 Chlorine pentafluoride CO Carbon monoxide CO2 Carbon dioxide Cl2O Dichlorine monoxide PCl5 Phosphorus pentachloride N2O5 Dinitrogen pentoxide 1. Fill in the table to indicate the number of atoms of each type in the molecular formula. -
Ozone Depletion, Greenhouse Gases, and Climate Change
DOCUMENT RESUME ED 324 229 SE 051 620 TITLE Ozone Depletion, Greenhouse Gaaes, and Climate Change. Proceedings of a Joint Symposium by theBoard on Atmospheric Sciences and Climate andthe Committee on Global Change, National ResearchCouncil (Washington, D.C., March 23, 1988). INSTITUTION National Academy of Sciences - National Research Council, Washington, D.C. SPONS AGENCY National Science Foundation, Washington, D.C. REPORT NO ISBN-0-309-03945-2 PUB DATE 90 NOTE 137p. AVAILABLE FROMNational Academy of Scences, National AcademyPress, 2101 Constitution Avenue, NW, Washington, DC 20418 ($20.00). PUB TYPE Collected Works Conference Proceedings (021) EDRS PRICE MF01 Plus Postage. PC Not Available from EDRS. DESCRIPTORS Air Pollution; *Climate; *Conservation(Environment); Depleted Resources; Earth Science; Ecology; *Environmental Education; *Environmental Influences; Global Approach; *Natural Resources; Science Education; Thermal Environment; World Affairs; World Problems IDENTIFIERS *Global Climate Change ABSTRACT The motivation for the organization of thissymposium was the accumulation of evidence from manysources, both short- and longterm,_that the global climate is in a state of change. Data which defy integrated explanation including temperature, ozone, methane, precipitation and other climate-related trendshave presented troubling problems for atmospheric sciencesince the 1980's. Ten papers from this symposium are presentedhere: (1) "Global Change and the Changing Atmosphere"(William C. Clark); (2) "Stratospheric Ozone Depletion: Global Processes"(Daniel L. Albritton); (3) "Stratospheric Czone Depletion: AntarcticProcesses" (Robert T. Watson); (4) "The Role of Halocarbons in Stratospheric Ozone Depletion" (F. Sherwood Rowland);(5) "Heterogenous Chemical Processes in Ozone Depletion" (Mario J. Molina);(6) "Free Radicals in the Earth's Atmosphere: Measurement andInterpretation" (James G. Anderson); (7) "Theoretical Projections of StratosphericChange Due to Increasing Greenhouse Gases and Changing OzoneConcentrations" (Jerry D. -
Example Exercise 8.1 Evidence for a Reaction
Example Exercise 8.1 Evidence for a Reaction Which of the following is experimental evidence for a chemical reaction? (a) Pouring vinegar on baking soda gives foamy bubbles. (b) Mixing two solutions produces insoluble particles. (c) Mixing two colorless solutions gives a yellow solution. (d) Mixing two solutions produces a temperature increase. Solution We can analyze each of these observations based on the criteria for a chemical reaction. (a) The bubbles produced indicate a chemical reaction is occurring. (b) The insoluble particles formed indicate a chemical reaction. (c) The yellow color produced indicates a chemical reaction. (d) The temperature increase indicates heat energy is being released and, thus, an exothermic chemical reaction. Practice Exercise What are four observations that a chemical reaction has occurred? Answers: (a) a gas is released; (b) a precipitate is produced; (c) a permanent color change is observed; (d) an energy change is noted Concept Exercise What four observations are evidence for a chemical reaction? Answer: See Appendix G. Introductory Chemistry: Concepts and Critical Thinking, 6th Edition © 2011 Pearson Education, Inc. Charles H. Corwin Example Exercise 8.2 Writing Chemical Equations Write a chemical equation for each of the following chemical reactions: (a) Mercury liquid and fluorine gas react to give solid mercury(II) fluoride. (b) Zinc metal reacts with sulfuric acid to give aqueous zinc sulfate and hydrogen gas. Solution To write the chemical equation, we must provide formulas and symbols for each substance. We can describe each of the preceding chemical reactions as follows: (a) Hg(l) + F2(g) → HgF2(s) (b) Zn(s) + H2SO4(aq) → ZnSO4(aq) + H2(g) Practice Exercise Write a chemical equation for each of the following chemical reactions: (a) Aqueous solutions of sodium iodide and silver nitrate yield silver iodide precipitate and aqueous sodium nitrate. -
Theoretical Photoabsorption Spectra of Cloocl and Cl2o
7278 J. Phys. Chem. A 2000, 104, 7278-7283 Theoretical Photoabsorption Spectra of ClOOCl and Cl2O A. Toniolo,† M. Persico,* and D. Pitea† Dipartimento di Chimica Fisica ed Elettrochimica, UniVersita` di Milano, Via Golgi 19, I-20133 Milano, Italy, and Dipartimento di Chimica e Chimica Industriale, UniVersita` di Pisa, Via Risorgimento 35, I-56126 Pisa, Italy ReceiVed: March 27, 2000; In Final Form: May 25, 2000 We calculated transition energies and oscillator strengths of ClOOCl and Cl2O in the Franck-Condon region with ab initio techniques. We describe 8 singlet excited states for ClOOCl and 13 excited states for Cl2O. The photoabsorption spectra are simulated by a semiclassical approach, which takes into account the vibrational phase space distribution in the ground state and the geometry dependence of excitation energies and transition dipoles. We present an unambiguous assignation of the available UV spectra, which is preliminary to the interpretation of the photochemistry of these compounds. 1. Introduction In the last fifteen years, the photochemistry of chlorine oxides has received considerable attention: the importance of the ozone loss catalytic cycles has made advisable to understand the photodissociation reactions of the chlorine-oxygen containing molecules present in the stratosphere.1-3 Among the important chlorine-oxygen compounds, the spectroscopy of ClO has been investigated theoretically by us and others,4-6 and rather complete potential energy surfaces for 7 ClO2 have been presented. ClOOCl and Cl2O have been paid less attention by computational chemists. It is now accepted that the most important catalytic cycle that results in ozone depletion in the Antarctic stratosphere starts with the self-reaction of ClO radicals and involves the formation of a chlorine peroxide ClOOCl molecule.8 The absorption of radiation breaks preferably one of the two Cl-O Figure 1. -
Dichlorine Monoxide
Dichlorine monoxide Other names: Chlorine monooxide; Chlorine monoxide; Chlorine monoxide (Cl2O); Chlorine oxide; Chlorine oxide (Cl2O); Cl2O; Dichlorine oxide; Dichloromonoxide; Dichloroxide; Hypochlorous anhydride. InChI: InChI=1S/Cl2O/c1-3-2 InChI Key: RCJVRSBWZCNNQT-UHFFFAOYSA-N Formula: Cl2O SMILES: ClOCl Molecular Weight: 86.90 CAS: 7791-21-1 Physical Properties Property Value Unit Source EA 1.30 ± 0.43 eV NIST Webbook ∆ G° -179.74 Joback Method f kJ/mol ∆ H° -207.03 Joback Method f gas kJ/mol ∆ H° 5.34 Joback Method fus kJ/mol ∆ H° 26.77 Joback Method vap kJ/mol IE 10.91 ± 0.02 eV NIST Webbook IE 10.91 ± 0.02 eV NIST Webbook IE 10.94 eV NIST Webbook IE 11.20 ± 0.10 eV NIST Webbook IE 11.02 eV NIST Webbook logP 1.31 Crippen Method oct/wat P 5836.07 Joback Method c kPa T 296.68 Joback Method boil K T 479.25 Joback Method c K T 171.83 Joback Method fus K V 0.15 3 Joback Method c m /kg-mol Temperature Dependent Properties Property Value Unit Temperature (K) Source C 47.60 J/mol×K 296.68 Joback Method p,gas η 0.00 Pa×s 296.68 Joback Method Sources Joback Method: https://en.wikipedia.org/wiki/Joback_method NIST Webbook: http://webbook.nist.gov/cgi/inchi/InChI=1S/Cl2O/c1-3-2 Crippen Method: http://pubs.acs.org/doi/abs/10.1021/ci990307l Legend C : Ideal gas heat capacity (J/mol×K). p,gas η: Dynamic viscosity (Pa×s). EA: Electron affinity (eV). ∆ G°: Standard Gibbs free energy of formation (kJ/mol). -
Significant Impact of Heterogeneous Reactions of Reactive Chlorine Species on Summertime Atmospheric Ozone and Free-Radical Form
Science of the Total Environment 693 (2019) 133580 Contents lists available at ScienceDirect Science of the Total Environment journal homepage: www.elsevier.com/locate/scitotenv Significant impact of heterogeneous reactions of reactive chlorine species on summertime atmospheric ozone and free-radical formation in north China Xionghui Qiu a,b,QiYingc,⁎, Shuxiao Wang a,b,⁎⁎, Lei Duan a,b, Yuhang Wang d,KedingLue,PengWangf, Jia Xing a,b, Mei Zheng g,MinjiangZhaoa,b, Haotian Zheng a,b, Yuanhang Zhang e,JimingHaoa,b a State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China b State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China c Zachry Department of Civil Engineering, Texas A&M University, College Station, TX, United States d School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA 30332, United States e State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University,Beijing,China f Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, 999077, Hong Kong, China g SKL-ESPC and BIC-ESAT, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China HIGHLIGHTS GRAPHICAL ABSTRACT • This work represents the first high reso- lution regional modeling to quantify the impact of chlorine chemistry on the ox- idation capacity in a polluted urban at- mosphere. • These heterogeneous reactions of reac- tive chlorine species increased the O3, OH, HO2 and RO2 concentrations signifi- cantly for some regions in the Beijing- Tianjin-Hebei (BTH) area. -
Chapter 7: Search for New Fire Suppressant Chemicals
Chapter 7: SEARCH FOR NEW FIRE J. Douglas Mather, Ph.D. SUPPRESSANT CHEMICALS Chemical Development Studies, Inc. Robert E. Tapscott, Ph.D. GlobeTech, Inc. TABLE OF CONTENTS 7.1 Fire Suppressant Replacement Knowledge Prior to the NGP .........................................612 7.1.1 Overview of Early Halon Replacement Efforts ....................................................612 7.1.2 Fire Suppressant Research – 1974 Through 1993.................................................613 7.1.3 DoD Technology Development Plan (1993 to 1997)............................................615 7.1.4 Advanced Agent Working Group (AAWG) .........................................................616 7.1.5 Summary: Alternative Agents and Selection Criteria Prior to the NGP ...............622 7.2 The NGP Approach to New Chemicals Screening..........................................................612 7.3 NGP Surveys of Inorganic Chemical Families................................................................612 7.3.1 Main Group Elements - Group I............................................................................626 7.3.2 Main Group Elements - Group II ..........................................................................627 7.3.3 Main Group Elements - Group III.........................................................................627 7.3.4 Main Group Elements - Group IV.........................................................................628 7.3.5 Main Group Elements - Group V..........................................................................634 -
Chapter 4 Nomenclature
Chapter 4 Nomenclature 1. A binary compound is one that contains only two elements. Examples are sodium chloride, water, and carbon dioxide. 2. compounds that contain a metal and a nonmetal; compounds containing two nonmetals 3. cation, anion 4. cation 5. The substance “sodium chloride” consists of an extended lattice array of sodium ions, Na+, and chloride ions, Cl–. Each sodium ion is surrounded by several chloride ions, and each chloride ion is surrounded by several sodium ions. We write the formula as NaCl to indicate the relative number of each ion in the substance. 6. a. sodium iodide b. calcium fluoride c. aluminum sulfide d. calcium bromide e. strontium oxide f. silver chloride [silver(I) chloride] g. cesium iodide h. lithium oxide 7. a. Incorrect; BaH2 is barium hydride. b. Incorrect; Na2O is sodium oxide. c. Correct d. Incorrect; SiO2 is silicon dioxide. e. Correct 8. a. Since each iodide ion has a 1– charge, the iron ion must have a 3+ charge: the name is iron(III) iodide. b. Since each chloride ion has a 1– charge, the manganese must have a 2+ charge: the name is manganese(II) chloride. c. Since the oxide ion has a 2– charge, the mercury ion must have a 2+ charge: the name is mercury(II) oxide. d. Since the oxide ion has a 2– charge, the copper atoms must each have a 1+ charge: the name is copper(I) oxide. e. Since the oxide ion has a 2– charge, the copper ion must have a 2+ charge: copper(II) oxide. f. -
What Are the Reactive Halogen Gases That Destroy Stratospheric Ozone?
What are the reactive halogen gases that destroy Q7 stratospheric ozone? The chlorine- and bromine-containing gases that enter the stratosphere arise from both human activities and natural processes. When exposed to ultraviolet radiation from the Sun, these halogen source gases are converted to more reactive gases that also contain chlorine and bromine. Some reactive gases act as chemical reservoirs which can then be converted into the most reactive gases, namely ClO and BrO. These most reactive gases participate in catalytic reactions that efficiently destroy ozone. Halogen-containing gases present in the stratosphere can be Reactive halogen gases. The chemical conversion of halogen divided into two groups: halogen source gases and reactive hal- source gases, which involves solar ultraviolet radiation and ogen gases (see Figure Q7-1). The source gases, which include other chemical reactions, produces a number of reactive halo- ozone-depleting substances (ODSs), are emitted at Earth’s gen gases. These reactive gases contain all of the chlorine and surface by natural processes and by human activities (see Q6). bromine atoms originally present in the source gases. The most Once in the stratosphere, the halogen source gases chemically important reactive chlorine- and bromine-containing gases that convert at different rates to form the reactive halogen gases. form in the stratosphere are shown in Figure Q7-1. Throughout The conversion occurs in the stratosphere instead of the tropo- the stratosphere, the most abundant are typically hydrogen sphere for most gases because solar ultraviolet radiation (a com- chloride (HCl) and chlorine nitrate (ClONO2). These two gases ponent of sunlight) is more intense in the stratosphere (see Q2). -
Tin Dioxide Nanowires and Carbon Nanotubes
Portland State University PDXScholar Dissertations and Theses Dissertations and Theses Winter 2-12-2016 One-Dimensional Nanostructure and Sensing Applications: Tin Dioxide Nanowires and Carbon Nanotubes Hoang Anh Tran Portland State University Follow this and additional works at: https://pdxscholar.library.pdx.edu/open_access_etds Part of the Chemistry Commons, Materials Science and Engineering Commons, and the Nanoscience and Nanotechnology Commons Let us know how access to this document benefits ou.y Recommended Citation Tran, Hoang Anh, "One-Dimensional Nanostructure and Sensing Applications: Tin Dioxide Nanowires and Carbon Nanotubes" (2016). Dissertations and Theses. Paper 2689. https://doi.org/10.15760/etd.2685 This Dissertation is brought to you for free and open access. It has been accepted for inclusion in Dissertations and Theses by an authorized administrator of PDXScholar. Please contact us if we can make this document more accessible: [email protected]. One-Dimensional Nanostructure and Sensing Applications: Tin Dioxide Nanowires and Carbon Nanotubes by Hoang Anh Tran A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Chemistry Dissertation Committee: Shankar Rananavare, Chair Carl Wamser Albert Benight Raj Solanki Erik Sanchez James Blackwell Portland State University 2016 Abstract The key challenge for a nanomaterial based sensor is how to synthesize in bulk quantity and fabricate an actual device with insightful understanding of operational mechanisms during performance. I report here effective, controllable methods that exploit the concepts of the “green approach” to synthesize two different one-dimensional nanostructures, including tin oxide nanowires and carbon nanotubes. The syntheses are followed by product characterization and sensing device fabrications as well as sensor performance understanding at the molecular level. -
The Chemistry of Chlorine Monoxide (Dichlorine Monoxide)
The Chemistry of Chlorine Monoxide (Dichlorine Monoxide) J. J. RENARDt and H. I. BOLKER’ Pulp and Paper Research Institute of Canada, Pointe Claire, Quebec, Canada H9R 3J9 Received December 9, 1974 (Revised Manuscript Received August 27, 1975) Contents 1. Introduction I. Introduction 487 In the first reported synthesis of chlorine monoxide (1834), 11. Preparation 488 A. J. Balard, a French chemist, prepared a concentrated solution A. Mercuric Oxide Method 488 of hypochlorous acid by treating an aqueous chlorine solution 6. Sodium Carbonate and Allied Methods 488 with mercuric oxide. Then, upon careful addition of anhydrous C. Preparationfrom Hypochlorous Acid Solutions 489 calcium nitrate, he observed the evolution of a gas. Its compo- 111. Analysis 489 sition was determined by Balard’-* and by Gay-Lu~sac,~who IV. Physical Properties 489 showed that on thermal decomposition the new compound A. General 489 yielded chlorine and oxygen in the volume ratio of 2 to 1. Since 6. Thermodynamic Properties 490 a vapor density of 86.92 was found, relative to hydrogen (=2), C. Solubility 490 the formula CI2O was assigned to the gas. 1. In Water 490 Chlorine monoxide is a compound of considerable scientific 2. In Carbon Tetrachloride 493 interest. As a simple triatomic molecule belonging to the C2, V. Structure and Spectrochemistry 493 symmetry group, C120 is a classical example of nonlinear XY2 A. Dipole Moment 493 molecules and has therefore been extensively studied by B. Ionization Potential-Mass Spectroscopy 494 spectroscopists. Also, conflicting reports on its stability have C. Molecular Geometry 494 stimulated many investigations of its thermal decomposition as D. -
Hydrogen Chloride-Induced Surface Disordering on Ice
Hydrogen chloride-induced surface disordering on ice V. Faye McNeill*†, Thomas Loerting‡§¶, Franz M. Geiger‡§ʈ, Bernhardt L. Trout*, and Mario J. Molina‡§** Departments of ‡Chemistry, §Earth, Atmospheric, and Planetary Sciences, and *Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139 Contributed by Mario J. Molina, May 4, 2006 Characterizing the interaction of hydrogen chloride (HCl) with gas phase. We find that trace amounts of HCl induce surface polar stratospheric cloud ice particles is essential for understanding change, which we interpret to be formation of a disordered the processes responsible for ozone depletion. We studied the surface region, on ice at a range of conditions that includes interaction of gas-phase HCl with ice between 243 and 186 K by stratospherically relevant temperatures and HCl partial pres- using (i) ellipsometry to monitor the ice surface and (ii) coated-wall sures. We show that the chlorine activation reaction of HCl with flow tube experiments, both with chemical ionization mass spec- ClONO2 on ice is enhanced in the presence of surface disorder, trometry detection of the gas phase. We show that trace amounts as is the uptake of gas-phase CH3COOH. These results impact of HCl induce formation of a disordered region, or quasi-liquid our understanding of the chemistry and physics of ice particles layer, at the ice surface at stratospheric temperatures. We also in the atmosphere. show that surface disordering enhances the chlorine activation reaction of HCl with chlorine nitrate (ClONO2) and also enhances Results acetic acid (CH3COOH) adsorption. These results impact our under- Figs. 1 and 2 show the ellipsometry signals during two studies of standing of the chemistry and physics of ice particles in the ice in the presence of HCl in the gas phase, (i) at constant HCl atmosphere.