"Electrochemistry in Nonaqueous Solutions"
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Addendum.Solubility
Addendum to Hebden: Chemistry 11 SOLUBILITY I. CALCULATING SOLUBILITY AND ION CONCENTRATIONS Once the mass of a substance present in 1 L of a solution has been experimentally measured, calculating the solubility of the substance is straightforward. EXAMPLE: It is experimentally found that 1.00 L of saturated AgBrO3(aq) contains 1.96 g of AgBrO3. What is the molar solubility of AgBrO3? (That is, what is the solubility expressed in moles per litre?) g 1mol –3 [AgBrO3] = 1.96 x = 8.31 x 10 M L 235 .8 g –3 EXAMPLE: The molar solubility of PbI2 is 1.37 x 10 M. Express this value in grams per litre. –3 mol 461.0 g g Solubility (g/L) = 1.37 x 10 x = 0.632 L 1mol L o EXAMPLE: It is experimentally found that 0.250 L of saturated CaCl2 contains 18.6 g of CaCl2 at 20 C. What is the molar solubility of CaCl2? 18.6 g 1mol [CaCl2] = x = 0.670 M 0 .250L 111 .1g Note: Unless otherwise indicated, assume all solutions are at a temperature of 25oC. EXERCISES: o 1. Aluminum fluoride, AlF3 , has a solubility of 5.59 g/L at 20 C. Express this solubility in moles per litre. o 2. Lead (II) chloride, PbCl2 , has a solubility of 0.99 g/100.0 mL at 20 C. Calculate the molar solubility of PbCl2 . –3 o 3. The molar solubility of MgCO3 is 1.26 x 10 M at 25 C. Express this value in grams per litre. –4 o 4. -
Kinetic and Equilibrium Acidities of Nitrocycloalkanes J
Kinetic and Equilibrium Acidities of Nitrocycloalkanes J. Org. Chem., Vol. 43, No. 16, 1978 3113 Acknowledgment. We are grateful to the National Science 13) M. Eigen, Angew, Chem., lnt. Ed. Engl., 3, l(1964). 14) E. Grunwald and D. Eustace, ref IO, Chapter 4,have shown that usually Foundation and the National Institutes of Health for support one or two water molecules separate the reactants in proton transfers of of this research. Comments of a referee and of Professor A. J. this type. Kresge were helpful in preparing a revised version of this 15) R. A. More O’Ferrall, ref IO, Chapter 8. 16) R. A. Ogg and M. Polyani, Trans. Faraday Soc., 31, 604 (1935). manuscript. 17) E. A. Moelwyn-Hughes and D. Glen, Roc. R. SOC.London, Ser. A,, 212, 260 (1952). References and Notes (18) C. D. Ritchie, “Solute-Solvent Interations”, J. F. Coetzee and C. 0. Ritchie, Eds., Marcel Dekker, New York, N.Y., 1969,Chapter 4,pp 266-268. (1) National Institutes of Health Fellow, 1967-1970. (19) R. A. Marcus, J. Phys. Chem., 72, 891 (1968). (2) R. P. Bell and D. M. Goodall, Proc. R. Soc.London, Ser. A, 294, 273 (1966); (20)Hydroxide (or alkoxide) ions are believed to be solvated by three tightly D. J. Barnes and R. P. Bell, ibid., 318,421 (1970);R. P. Bell and B. J. Cox, bound (inner sphere) water molecules. [The additional (outer sphere) water J. Chem. SOC.6, 194 (1970). molecules that are also present are not shown.] Judging from the energy (3) V. -
Development Team
Paper No: 16 Environmental Chemistry Module: 01 Environmental Concentration Units Development Team Prof. R.K. Kohli Principal Investigator & Prof. V.K. Garg & Prof. Ashok Dhawan Co- Principal Investigator Central University of Punjab, Bathinda Prof. K.S. Gupta Paper Coordinator University of Rajasthan, Jaipur Prof. K.S. Gupta Content Writer University of Rajasthan, Jaipur Content Reviewer Dr. V.K. Garg Central University of Punjab, Bathinda Anchor Institute Central University of Punjab 1 Environmental Chemistry Environmental Environmental Concentration Units Sciences Description of Module Subject Name Environmental Sciences Paper Name Environmental Chemistry Module Name/Title Environmental Concentration Units Module Id EVS/EC-XVI/01 Pre-requisites A basic knowledge of concentration units 1. To define exponents, prefixes and symbols based on SI units 2. To define molarity and molality 3. To define number density and mixing ratio 4. To define parts –per notation by volume Objectives 5. To define parts-per notation by mass by mass 6. To define mass by volume unit for trace gases in air 7. To define mass by volume unit for aqueous media 8. To convert one unit into another Keywords Environmental concentrations, parts- per notations, ppm, ppb, ppt, partial pressure 2 Environmental Chemistry Environmental Environmental Concentration Units Sciences Module 1: Environmental Concentration Units Contents 1. Introduction 2. Exponents 3. Environmental Concentration Units 4. Molarity, mol/L 5. Molality, mol/kg 6. Number Density (n) 7. Mixing Ratio 8. Parts-Per Notation by Volume 9. ppmv, ppbv and pptv 10. Parts-Per Notation by Mass by Mass. 11. Mass by Volume Unit for Trace Gases in Air: Microgram per Cubic Meter, µg/m3 12. -
The Vertical Distribution of Soluble Gases in the Troposphere
UC Irvine UC Irvine Previously Published Works Title The vertical distribution of soluble gases in the troposphere Permalink https://escholarship.org/uc/item/7gc9g430 Journal Geophysical Research Letters, 2(8) ISSN 0094-8276 Authors Stedman, DH Chameides, WL Cicerone, RJ Publication Date 1975 DOI 10.1029/GL002i008p00333 License https://creativecommons.org/licenses/by/4.0/ 4.0 Peer reviewed eScholarship.org Powered by the California Digital Library University of California Vol. 2 No. 8 GEOPHYSICAL RESEARCHLETTERS August 1975 THE VERTICAL DISTRIBUTION OF SOLUBLE GASES IN THE TROPOSPHERE D. H. Stedman, W. L. Chameides, and R. J. Cicerone Space Physics Research Laboratory Department of Atmospheric and Oceanic Science The University of Michigan, Ann Arbor, Michigan 48105 Abstrg.ct. The thermodynamic properties of sev- Their arg:uments were based on the existence of an eral water-soluble gases are reviewed to determine HC1-H20 d•mer, but we consider the conclusions in- the likely effect of the atmospheric water cycle dependeht of the existence of dimers. For in- on their vertical profiles. We find that gaseous stance, Chameides[1975] has argued that HNO3 HC1, HN03, and HBr are sufficiently soluble in should follow the water-vapor mixing ratio gradi- water to suggest that their vertical profiles in ent, based on the high solubility of the gas in the troposphere have a similar shape to that of liquid water. In this work, we generalize the water va•or. Thuswe predict that HC1,HN03, and moredetailed argumentsof Chameides[1975] and HBr exhibit a steep negative gradient with alti- suggest which species should exhibit this nega- tude roughly equal to the altitude gradient of tive gradient and which should not. -
Package 'Marelac'
Package ‘marelac’ February 20, 2020 Version 2.1.10 Title Tools for Aquatic Sciences Author Karline Soetaert [aut, cre], Thomas Petzoldt [aut], Filip Meysman [cph], Lorenz Meire [cph] Maintainer Karline Soetaert <[email protected]> Depends R (>= 3.2), shape Imports stats, seacarb Description Datasets, constants, conversion factors, and utilities for 'MArine', 'Riverine', 'Estuarine', 'LAcustrine' and 'Coastal' science. The package contains among others: (1) chemical and physical constants and datasets, e.g. atomic weights, gas constants, the earths bathymetry; (2) conversion factors (e.g. gram to mol to liter, barometric units, temperature, salinity); (3) physical functions, e.g. to estimate concentrations of conservative substances, gas transfer and diffusion coefficients, the Coriolis force and gravity; (4) thermophysical properties of the seawater, as from the UNESCO polynomial or from the more recent derivation based on a Gibbs function. License GPL (>= 2) LazyData yes Repository CRAN Repository/R-Forge/Project marelac Repository/R-Forge/Revision 205 Repository/R-Forge/DateTimeStamp 2020-02-11 22:10:45 Date/Publication 2020-02-20 18:50:04 UTC NeedsCompilation yes 1 2 R topics documented: R topics documented: marelac-package . .3 air_density . .5 air_spechum . .6 atmComp . .7 AtomicWeight . .8 Bathymetry . .9 Constants . 10 convert_p . 11 convert_RtoS . 11 convert_salinity . 13 convert_StoCl . 15 convert_StoR . 16 convert_T . 17 coriolis . 18 diffcoeff . 19 earth_surf . 21 gas_O2sat . 23 gas_satconc . 25 gas_schmidt . 27 gas_solubility . 28 gas_transfer . 31 gravity . 33 molvol . 34 molweight . 36 Oceans . 37 redfield . 38 ssd2rad . 39 sw_adtgrad . 40 sw_alpha . 41 sw_beta . 42 sw_comp . 43 sw_conserv . 44 sw_cp . 45 sw_dens . 47 sw_depth . 49 sw_enthalpy . 50 sw_entropy . 51 sw_gibbs . 52 sw_kappa . -
The Air Oxidation of 4,6-Di (2-Phenyl-2-Propyl) Pyrogallol. Spectroscopic and Kinetic Studies of the Intermediates
Carlsberg Res. Commun. Vol. 42, p. 11-25 THE AIR OXIDATION OF 4,6-DI (2-PHENYL-2-PROPYL) PYROGALLOL. SPECTROSCOPIC AND KINETIC STUDIES OF THE INTERMEDIATES. by HENRY I. ABRASH Department of Chemistry, Carlsberg Laboratory Gamle Carlsbergvej 10 - DK-2500 Copenhagen, Valby~ 1) Current address: Department of Chemistry, California State University at Northridge, Northridge, California 91324, USA Key words: 4,6-di (2-phenyl-2-propyl) pyrogallol, consecutive reactions, oxidation, oxygen, pH, quinone, semiquinone, spectra Two colored extinction bands, one with ~'max near 520 nm and the other near 770 nm, form and decay during air oxidations of 4,6-di(2-phenyl-2-propyl)pyrogallol in alkaline methanol. The 770 nm band appears to be due to the semiquinone monoanion while the extinction near 500 nm is thought to be due to both the semiquinone and 3-hydroxy-o-quinone. Although the rates of formation and decay of the two bands are indistinguishable in the presence of excess dissolved oxygen, the 770 nm band disappears slightly before the 500 nm extinction when the pyrogallol reactant is initially in excess of the dissolved oxygen. Except at high methoxide concentrations, the kinetics indicate a system of two consecutive reactions with pseudo first-order rate constants k~ and k 2. The pH' dependence of k~ indicates that the neutral pyrogallol, its monoanion and dianion all react, the rate increasing with the negative charge of the species. The k2/k~ ratio is constant at 5 from pH' 11 to 16. Extinction coefficients at both wavelengths increase with pH'. The 770 nm extinction disappears immediately after acidification while the 500 nm extinction decays at a rate consistent with oxidation. -
Chemistry Curriculum L1
1 CHEMISTRY The Nature of Chemistry Topic(s) Concepts Competencies (Eligible Anchor Descriptions Vocabulary Textbook Duration (with Standards) Content) Pages (in days) The Scientific 3.2.10.A6: CHEM.A.1.1.1: CHEM.A.1.1: The Nature of Chemistry L1: Ch 1 (p3-27) 2-5 Method • Compare and contrast • Classify physical or • Identify and describe how Analytical chemistry scientific theories. chemical changes within a observable and measurable Biochemistry Laboratory • Know that both direct system in terms of matter properties can be used to Chemistry Procedure(s) and indirect observations and/or energy. classify and describe matter Inorganic chemistry and Safety are used by scientists to and energy. Organic chemistry study the natural world CHEM.A.1.1.2: Physical chemistry The Metric and universe. • Classify observations as Science System, • Identify questions and qualitative and/or Technology Significant concepts that guide quantitative. Figures, and scientific investigations. Scientific Methods and L1 and L2: 2-5 Measurement • Formulate and revise CHEM.A.1.1.3: Laboratory Safety & Teacher and explanations and models • Utilize significant figures to Procedures department using logic and evidence. communicate the Control generated • Recognize and analyze uncertainty in a quantitative Control experiment materials; Flinn alternative explanations observation. Dependent variable Scientific Safetly and models. Erlenmeyer flask (E-flask) Contract • Explain the importance of Graduated cylinder accuracy and precision in Hypothesis making valid Independent variable measurements. Laboratory balance Laboratory burner 3.2.C.A6: Law • Examine the status of Observation existing theories. Science Scientific method • Evaluate experimental Theory information for relevance Variable and adherence to Laboratory equipment science processes. -
Calculation Exercises with Answers and Solutions
Atmospheric Chemistry and Physics Calculation Exercises Contents Exercise A, chapter 1 - 3 in Jacob …………………………………………………… 2 Exercise B, chapter 4, 6 in Jacob …………………………………………………… 6 Exercise C, chapter 7, 8 in Jacob, OH on aerosols and booklet by Heintzenberg … 11 Exercise D, chapter 9 in Jacob………………………………………………………. 16 Exercise E, chapter 10 in Jacob……………………………………………………… 20 Exercise F, chapter 11 - 13 in Jacob………………………………………………… 24 Answers and solutions …………………………………………………………………. 29 Note that approximately 40% of the written exam deals with calculations. The remainder is about understanding of the theory. Exercises marked with an asterisk (*) are for the most interested students. These exercises are more comprehensive and/or difficult than questions appearing in the written exam. 1 Atmospheric Chemistry and Physics – Exercise A, chap. 1 – 3 Recommended activity before exercise: Try to solve 1:1 – 1:5, 2:1 – 2:2 and 3:1 – 3:2. Summary: Concentration Example Advantage Number density No. molecules/m3, Useful for calculations of reaction kmol/m3 rates in the gas phase Partial pressure Useful measure on the amount of a substance that easily can be converted to mixing ratio Mixing ratio ppmv can mean e.g. Concentration relative to the mole/mole or partial concentration of air molecules. Very pressure/total pressure useful because air is compressible. Ideal gas law: PV = nRT Molar mass: M = m/n Density: ρ = m/V = PM/RT; (from the two equations above) Mixing ratio (vol): Cx = nx/na = Px/Pa ≠ mx/ma Number density: Cvol = nNav/V 26 -1 Avogadro’s -
The Role of Hydrogen Bonding in Paracetamol–Solvent and Paracetamol–Hydrogel Matrix Interactions
materials Article The Role of Hydrogen Bonding in Paracetamol–Solvent and Paracetamol–Hydrogel Matrix Interactions Marta Miotke-Wasilczyk *, Marek Józefowicz * , Justyna Strankowska and Jerzy Kwela Insitute of Experimental Physics, Faculty of Mathematics, Physics and Informatics, University of Gda´nsk, Wita Stwosza 57, 80-308 Gda´nsk,Poland; [email protected] (J.S.); [email protected] (J.K.) * Correspondence: [email protected] (M.M.-W.); [email protected] (M.J.) Abstract: The photophysical and photochemical properties of antipyretic drug – paracetamol (PAR) and its two analogs with different substituents (acetanilide (ACT) and N-ethylaniline (NEA)) in 14 solvents of different polarity were investigated by the use of steady–state spectroscopic technique and quantum–chemical calculations. As expected, the results show that the spectroscopic behavior of PAR, ACT, and NEA is highly dependent on the nature of the solute–solvent interactions (non- specific (dipole-dipole) and specific (hydrogen bonding)). To characterize these interactions, the multiparameter regression analysis proposed by Catalán was used. In order to obtain a deeper insight into the electronic and optical properties of the studied molecules, the difference of the dipole moments of a molecule in the ground and excited state were determined using the theory proposed by Lippert, Mataga, McRae, Bakhshiev, Bilot, and Kawski. Additionally, the influence of the solute polarizability on the determined dipole moments was discussed. The results of the solvatochromic studies were related to the observations of the release kinetics of PAR, ACT, and NEA from polyurethane hydrogels. The release kinetics was analyzed using the Korsmayer-Peppas and Hopfenberg models. -
Ettore Majorana and the Birth of Autoionization
Ettore Majorana and the birth of autoionization E. Arimondo∗,† Charles W. Clark,‡ and W. C. Martin§ National Institute of Standards and Technology Gaithersburg, MD 20899, USA (Dated: May 19, 2009) Abstract In some of the first applications of modern quantum mechanics to the spectroscopy of many-electron atoms, Ettore Majorana solved several outstanding problems by developing the theory of autoionization. Later literature makes only sporadic refer- ences to this accomplishment. After reviewing his work in its contemporary context, we describe subsequent developments in understanding the spectra treated by Ma- jorana, and extensions of his theory to other areas of physics. We find many puzzles concerning the way in which the modern theory of autoionization was developed. ∗ Permanent address: Dipartimento di Fisica E. Fermi, Universit`adi Pisa, Italy †Electronic address: [email protected] ‡Electronic address: [email protected] §Electronic address: [email protected] 1 Contents I.Introduction 2 II.TheState of Atomic Spectroscopy circa 1931 4 A.Observed Spectra 4 B.Theoriesof Unstable Electronic States 6 III.Symmetry Considerations for Doubly-Excited States 7 IV.Analyses of the Observed Double-Excitation Spectra 8 A.Double Excitation in Helium 8 B.TheIncomplete np2 3P Terms in Zinc, Cadmium, and Mercury 9 V.Contemporary and Subsequent Work on Autoionization 12 A.Shenstone’s Contemporary Identification of Autoionization 12 B.Subsequent foundational work on autoionization 13 VI.Continuing Story of P − P0 Spectroscopy for Zinc, Cadmium, and Mercury 14 VII.Continuing Story of Double Excitation in Helium 16 VIII.Autoionization as a pervasive effect in physics 18 Acknowledgments 19 References 19 Figures 22 I. -
Solvent Deuterium Isotope Effect on Hydrolysis of Nd3+ Ion , and As Was
Notizen 1493 Solvent Deuterium Isotope Effect on Hydrolysis Experimental of Nd3+ Ion Reagents and apparatus A neodymium perchlorate sample solution and Mastjnobu Ma e d a *, T oshihiko A m ay a , and other reagents used were prepared and analyzed H id e t a k e K ak iha na according to the same procedures as those in the *Department of Applid Chemistry, previous papers5-6. Nagoya Institute of Technology, All the apparatus employed were the same as Gokiso, Showa-ku, Nagoya 466, Japan those in Ref. 7. Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, Preparation of a test solution O-okayama, Meguro-ku, Tokyo 152, Japan A test solution was prepared as follows. A (Z. Naturforsch. 32 b, 1493-1495 [1977]; received August 30, 1977) slightly acidic neodymium perchlorate solution, which had been freed from CO 2 by passing purified Deuterium Isotope Effect, Formation Constant, Heavy Water, Hydrolysis, Neodymium Ion N2 gas, was electrolyzed to reduce L+ ions by using a d. c. power supply until precipitates appeared. In order to saturate the solution with Nd(OL )3 precipi The hydrolysis equilibria of Nd3+ ion in tates the mixture was stirred with a magnetic rod light- and heavy-water solutions containing for two days. The precipitates of Nd(OL )3 were 3 mol dm -3 (Li)C104 as an ionic medium were removed by filtration with G 4 glass filters. All the studied at 25 °C by measuring the lyonium- procedures were carried out under an atmosphere ion concentration with a glass electrode. of N 2 gas in a room kept at 25 ± 1 °C. -
Auger Cascades in Resonantly Excited Neon
Auger cascades in resonantly excited neon masterarbeit zur Erlangung des akademischen Grades „Master of Science“ eingereicht bei der Physikalisch-Astronomischen Fakultät der Friedrich-Schiller-Universität Jena von Sebastian Stock geboren am 21. März 1993 in Aalen Jena, März 2017 Die in dieser Arbeit präsentierten Ergebnisse wurden ebenfalls in dem folgenden Artikel veröentlicht: S. Stock, R. Beerwerth, and S. Fritzsche. “Auger cascades in resonantly excited neon”. To be submitted. Erstgutachter: Prof. Dr. Stephan Fritzsche Zweitgutachter: Priv.-Doz. Dr. Andrey Volotka Abstract ¿e Auger cascades following the resonant 1s → 3p and 1s → 4p excitation of neutral neon are studied theoretically. In order to accurately predict Auger electron spectra, shake probabilities, ion yields, and the population of nal states, the complete cascade of decays from neutral to doubly-ionized neon is simulated by means of extensive mcdf calculations. Experimentally known values for the energy levels of neutral, singly and doubly ionized neon are utilized in order to further improve the simulated spectra. ¿e obtained results are compared to experimental ndings. For the most part, quite good agreement between theory and experiment is found. However, for the lifetime widths of certain energy levels of Ne+, larger dierences between the calculated values and the experiment are found. It is presumed that these discrepancies originate from the approximations that are utilized in the calculations of the Auger amplitudes. Contents 1 Introduction1 2 Overview of the Auger cascades3 3 Theory 7 3.1 Calculation of Auger amplitudes........................7 3.2 ¿e mcdf method.................................8 3.3 Shake processes and the biorthonormal transformation...........9 4 Calculations 11 4.1 Bound state wave function generation....................