A Study of Hydrogen Exchange in Benzene And
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Proton Transfer Reaction in Water: Hydronium Ion Formation
Advanced Journal of Chemistry-Section A, 2020, 3(3), 255–258 Available online at : www.ajchem-a.com ISSN Online: 2645-5676 DOI: 10.33945/SAMI/AJCA.2020.3.2 Short Communication Proton Transfer Reaction in Water: Hydronium Ion Formation In Sang Leea, Sitansu Sekhar Nandab,* a Research Division, Divine Lab Limited, Seoul, South Korea b Department of Chemistry, Myongji University, Yongin, South Korea A R T I C L E I N F O A B S T R A C T Received: 28 June 2019 The current ongoing scientific debate deals with accumulation of hydronium Revised: 07 August 2019 ions (H3O+) on water surface. Elevated interfacial concentration measured by Accepted: 31 August 2019 using Raman spectroscopy. A strong surface affinity of H3O+ indicated by Raman Available online: 03 September 2019 spectroscopy under similar conditions. Ion adsorption phenomena, H3O+ formation and its structural activity emphasized in our study. Asymmetric water ion adsorption clearly observed in our research. K E Y W O R D S Raman spectroscopy Hydronium Water Infrared spectroscopy G R A P H I C A L A B S T R A C T * Corresponding author's E-mail address: [email protected] Proton Transfer Reaction in Water: Hydronium… 256 Introduction employed for recording Raman spectra with 2– 10 s acquisition time. A scanning area of 30 μm × In nature, interfacial charge formation is 30 μm was applied to avoid laser damage to known as a ubiquitous phenomenon. water. Fundamental mechanism of interfacial charge formation related with its identification. Results and discussions Researchers have been attracted for charge formation development of appropriate models. -
Chemistry 20 - Unit 2 - Ph and Poh Notes Name: ______+ - [H3O ] and [OH ]
Chemistry 20 - Unit 2 - pH and pOH Notes Name: _________________________________________ + - [H3O ] and [OH ] + - + - In water both H3O and OH exist H2O + H2O ⇌ H3O + OH + - -14 These concentrations exist in a balanced relationship [H3O ][OH ] = 1.00 x 10 + - This relationship is inversely related ↑ [H3O ] = ↓ [OH ] Example 1: -4 What is the hydroxide ion concentration in a solution with a hydronium ion concentration of 2.59 x 10 M ? + - -14 [H3O ][OH ] = 1.00 x 10 −14 − 1.00×10 [OH ] = + [H3O ] −14 [OH−] = 1.00×10 = 3.86 × 10−11 2.59×10−4 Example 2: If 2.50 g of NaOH was dissolved in water to produce 500mL of solution, what would be the concentration of hydronium and hydroxide ions in solution? + - NaOH ⟶ Na + OH − mol 1 mol 1 [OH ] L = 2.50 g × 40 g × 0.500 L = 0.125 M + - -14 [H3O ][OH ] = 1.00 x 10 −14 −14 [H O+] = 1.00×10 = 1.00×10 = 8.0 × 10−14M 3 [OH−] 1.25 pH Review + pH = − log[H3O ] + −pH [H3O ] = 10 Example 3: What is the pH of a solution of 0.159 M HCl? + - HCl ⟶ H + Cl + pH = − log[H3O ] pH = − log[0.159 M] pH = 0.799 Example 4: What is the hydronium and hydroxide ion concentration of a solution with a pH of 2.42? + −pH −2.42 [H3O ] = 10 = 10 = 0.0038 M + - -14 [H3O ][OH ] = 1.00 x 10 −14 −14 − 1.00×10 1.00×10 −12 [OH ] = + = = 2.63 × 10 M [H3O ] 0.0038 M pOH - Power of OH Since: + - -14 [H3O ][OH ] = 1.00 x 10 Can take the “log” of both sides… pOH = − log[OH−] + - -14 -log([H3O ][OH ]) = -log(1.00 x 10 ) − −pOH [OH ] = 10 + - + - And -log([H3O ][OH ]) = -log[H3O ] + -log[OH ] Therefore… pH + pOH = 14 Example 5: A solution has a pH of 5.750. -
A General Chemical Method for the Preparation of The
Det Kgl . Danske Videnskabernes Selskab . Mathematisk-fysiske Meddelelser. XV, 13. A GENERAL CHEMICAL METHO D FOR THE PREPARATION OF TH E DEUTERATED BENZENE S B y A . LANGSETH AND A . KLIT KØBENHAVN LEVIN & MUNKSGAAHI? EJNAR MUNKSGA4RD 1937 Printed in Denmark . Bianco Lunos Bogtrykkeri A/S . Survey of the Method . he Raman spectra of the deuterium derivatives of ben- T zene should furnish valuable information concerning the internal vibrations of the benzene molecule, and from these one should also be able to make direct inferences concerning the structure of benzene. We have therefore prepared each of the derivatives in pure form and hav e investigated their spectra . In this paper we shall report only the methods of preparation . The introduction of deuterium into the benzene nucleus has usually been effected by exchange between benzen e and some deuterium compound, with or without a catalyst . The exchange method is quite satisfactory for preparin g hexadeuterobenzene . For the preparation of the intermediat e deuterium derivatives in pure form, however, the method of direct exchange is not applicable, since one can obtai n thereby only mixtures of the various compounds . It is therefore necessary to resort to chemical procedures which can be depended upon to introduce deuterium into definit e places in the ring . Two such procedures which immediatel y suggest themselves are : (1) the decarboxylation of the vari- ous calcium benzene-carboxylates with Ga(OD)2, and (2) the replacement of halogen atoms with deuterium by mean s of a Grignard reaction. The first of these methods was used by EILENMEYE R (Hely. -
Adapting Neural Machine Translation to Predict IUPAC Names from a Chemical Identifier
Translating the molecules: adapting neural machine translation to predict IUPAC names from a chemical identifier Jennifer Handsel*,a, Brian Matthews‡,a, Nicola J. Knight‡,b, Simon J. Coles‡,b aScientific Computing Department, Science and Technology Facilities Council, Didcot, OX11 0FA, UK. bSchool of Chemistry, Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, SO17 1BJ, UK. KEYWORDS seq2seq, InChI, IUPAC, transformer, attention, GPU ABSTRACT We present a sequence-to-sequence machine learning model for predicting the IUPAC name of a chemical from its standard International Chemical Identifier (InChI). The model uses two stacks of transformers in an encoder-decoder architecture, a setup similar to the neural networks used in state-of-the-art machine translation. Unlike neural machine translation, which usually tokenizes input and output into words or sub-words, our model processes the InChI and predicts the 1 IUPAC name character by character. The model was trained on a dataset of 10 million InChI/IUPAC name pairs freely downloaded from the National Library of Medicine’s online PubChem service. Training took five days on a Tesla K80 GPU, and the model achieved test-set accuracies of 95% (character-level) and 91% (whole name). The model performed particularly well on organics, with the exception of macrocycles. The predictions were less accurate for inorganic compounds, with a character-level accuracy of 71%. This can be explained by inherent limitations in InChI for representing inorganics, as well as low coverage (1.4 %) of the training data. INTRODUCTION The International Union of Pure and Applied Chemistry (IUPAC) define nomenclature for both organic chemistry2 and inorganic chemistry.3 Their rules are comprehensive, but are difficult to apply to complicated molecules. -
H3O+ Tof-CIMS
Atmos. Meas. Tech., 9, 2735–2752, 2016 www.atmos-meas-tech.net/9/2735/2016/ doi:10.5194/amt-9-2735-2016 © Author(s) 2016. CC Attribution 3.0 License. A high-resolution time-of-flight chemical ionization mass C spectrometer utilizing hydronium ions (H3O ToF-CIMS) for measurements of volatile organic compounds in the atmosphere Bin Yuan1,2, Abigail Koss1,2,3, Carsten Warneke1,2, Jessica B. Gilman1, Brian M. Lerner1,2, Harald Stark2,3,4, and Joost A. de Gouw1,2,3 1NOAA Earth System Research Laboratory (ESRL), Chemical Sciences Division, Boulder, CO, USA 2Cooperative Institute for Research in Environmental Sciences, University of Colorado at Boulder, Boulder, CO, USA 3Department of Chemistry and Biochemistry, University of Colorado at Boulder, CO, USA 4Aerodyne Research Inc., Billerica, MA 01821, USA Correspondence to: Bin Yuan ([email protected]) Received: 20 January 2016 – Published in Atmos. Meas. Tech. Discuss.: 9 February 2016 Revised: 17 May 2016 – Accepted: 9 June 2016 – Published: 1 July 2016 Abstract. Proton transfer reactions between hydronium ions research aircraft for the SONGNEX campaign in spring of C (H3O / and volatile organic compounds (VOCs) provide a 2015. The measured mixing ratios of several aromatics from C fast and highly sensitive technique for VOC measurements, the H3O ToF-CIMS agreed within ±10 % with independent leading to extensive use of proton-transfer-reaction mass gas chromatography measurements from whole air samples. spectrometry (PTR-MS) in atmospheric research. Based on Initial results from the SONGNEX measurements demon- C the same ionization approach, we describe the development strate that the H3O ToF-CIMS data set will be valuable for of a high-resolution time-of-flight chemical ionization mass the identification and characterization of emissions from var- C spectrometer (ToF-CIMS) utilizing H3O as the reagent ious sources, investigation of secondary formation of many C ion. -
UC San Diego Dissertation
UNIVERSITY OF CALIFORNIA, SAN DIEGO Enhancing Natural Products Structural Dereplication and Elucidation with Deep Learning Based Nuclear Magnetic Resonance Techniques A dissertation submitted in partial satisfaction of the requirements for the degree Doctor of Philosophy in NanoEngineering by Chen Zhang Committee in charge: William H. Gerwick, Chair Garrison W. Cottrell, Co-Chair Gaurav Arya Seth M. Cohen Chambers C. Hughes Preston B. Landon Liangfang Zhang 2017 Copyright Chen Zhang, 2017 All rights reserved The Dissertation of Chen Zhang is approved, and it is acceptable in quality and form for publication on microfilm and electronically: ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ Co-Chair ____________________________________________ Chair University of California, San Diego 2017 iii DEDICATION I dedicate my dissertation work to my family and many friends. A special feeling of gratitude to my beloved parents, Jianping Zhao and Xiaojing Zhang whose words of encouragement and push for tenacity ring in my ears. My cousin Min Zhang has never left my side and is very special. I also dedicate this dissertation to my mentors who have shown me fascinating views of the world throughout the process, and those who have walked me through the valley of the shadow of frustration. I will always appreciate all they have done, especially Bill Gerwick, Gary Cottrell and Preston Landon for showing me the gate to new frontiers, Sylvia Evans, Pieter Dorrestein, Shu Chien, Liangfang Zhang, and Gaurav Arya for their great encouragement, and Wood Lee and Yezifeng for initially showing me the value of freedom, and continuously answering my questions regarding social sciences, humanities, literature, and arts. -
Broensted Acids and Bases: They Are Not Substances but Molecules Or Ions!
AJCE, 2014, 4(4), ISSN 2227-5835 BROENSTED ACIDS AND BASES: THEY ARE NOT SUBSTANCES BUT MOLECULES OR IONS! Hans-Dieter Barke Institute of Chemistry Didactics, University of Muenster, Germany [email protected] Nina Harsch Centre for Teacher Education, University of Muenster, Germany [email protected] ABSTRACT For chemistry education we are discussing mainly two concepts of acids and bases: theories of Arrhenius and Broensted. For the first theory, dissociation into ions is generally discussed: acidic solutions contain H +(aq) ions, alkaline solutions contain OH -(aq) ions. This theory therefore deals with substances, which are referred toas acids and bases – it would be even better to take the logical names "acidic and alkaline solutions". If both solutions are mixed + - in equivalent quantities, the H (aq) ions react with OH (aq) ions to form H 2O molecules, while the other ions remain in solution (in exceptional cases an insoluble salt may precipitate: sulfuric acid solution reacts with barium chloride solution to solid white barium sulfate and water). The Broensted theory defines proton transfer: a molecule or an ion transfers a proton to another molecule or ion, two conjugated acid-base pairs are involved. Thus, Broensted acids and bases are no more substances, but individual types of particles. Due to the autoionization of H 2O molecules (not "autoionization of water"), the following equilibrium exists: + - H2O + H 2O D H3O (aq) + OH (aq) + Through this protolysis it is more advantageous to argue rather with H 3O (aq) ions than with H +(aq) ions. In this theory there are still ampholyte particles which react as acid or as base - particles depending on the reaction partners: H 2O molecules, NH 3molecules , HSO 4 ions – water, ammonia or sodium hydrogen sulfate cannot be regarded asampholytes. -
An Organic/Inorganic Electrode-Based Hydronium-Ion Battery ✉ Zhaowei Guo1, Jianhang Huang1, Xiaoli Dong 1, Yongyao Xia1, Lei Yan1, Zhuo Wang1 & Yonggang Wang 1
ARTICLE https://doi.org/10.1038/s41467-020-14748-5 OPEN An organic/inorganic electrode-based hydronium-ion battery ✉ Zhaowei Guo1, Jianhang Huang1, Xiaoli Dong 1, Yongyao Xia1, Lei Yan1, Zhuo Wang1 & Yonggang Wang 1 Hydronium-ion batteries are regarded as one of the most promising energy technologies as next-generation power sources, benefiting from their cost effectivity and sustainability merits. Herein, we propose a hydronium-ion battery which is based on an organic pyrene- 1234567890():,; 4,5,9,10-tetraone anode and an inorganic MnO2@graphite felt cathode in an acid electrolyte. 2+ Its operation involves a quinone/hydroquinone redox reaction on anode and a MnO2/Mn + conversion reaction on cathode, in parallel with the transfer of H3O between two electrodes. The distinct operation mechanism affords this hydronium-ion battery an energy density up to 132.6 Wh kg−1 and a supercapacitor-comparable power density of 30.8 kW kg−1, along with a long-term cycling life over 5000 cycles. Furthermore, surprisingly, this hydronium-ion battery works well even with a frozen electrolyte under −40 °C, and superior rate performance and cycle stability remain at −70 °C. 1 Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Institute of New Energy, iChEM (Collaborative ✉ Innovation Centre of Chemistry for Energy Materials), Fudan University, Shanghai 200433, China. email: [email protected] NATURE COMMUNICATIONS | (2020) 11:959 | https://doi.org/10.1038/s41467-020-14748-5 | www.nature.com/naturecommunications 1 ARTICLE NATURE COMMUNICATIONS | https://doi.org/10.1038/s41467-020-14748-5 ithium ion batteries (LIBs) using organic electrolytes have 2 e– 2 e– been extensively used to power various portable electronics L Mn2+ and electric vehicles (EVs) because of their desirable elec- PTO Cathode 1–9 +2 H O+ +4 H O+ trochemical performance . -
The Nature of the H3O Hydronium Ion in Benzene and Chlorinated Hydrocarbon Solvents
Published on Web 01/25/2006 + The Nature of the H3O Hydronium Ion in Benzene and Chlorinated Hydrocarbon Solvents. Conditions of Existence and Reinterpretation of Infrared Data Evgenii S. Stoyanov,* Kee-Chan Kim, and Christopher A. Reed* Contribution from the Department of Chemistry, UniVersity of California, RiVerside, California 92521 Received July 28, 2005; E-mail: [email protected] + Abstract: Salts of the C3v symmetric hydronium ion, H3O , have been obtained in the weakly basic solvents benzene, dichloromethane, and 1,2-dichloroethane. This is made possible by using carborane counterions - of the type CHB11R5X6 (R ) H, Me, Cl; X ) Cl, Br, I) because they combine the three required properties of a suitable counterion: very low basicity, low polarizability, and high chemical stability. The existence of + the H3O ion requires the formation of three more-or-less equivalent, medium-to-strong H-bonds with solvent - or anion bases. With the least basic anions such as CHB11Cl11 , IR spectroscopy indicates that C3v symmetric + trisolvates of formulation [H3O ‚3Solv] are formed with chlorocarbon solvents and benzene, the latter with the formation of π bonds. When the solvents and anions have comparable basicity, contact ion pairs of the + type [H3O ‚nSolv‚Carborane] are formed and close to C3v symmetry is retained. The conditions for the + existence of the H3O ion are much more exacting than previously appreciated. Outside of the range of solvent basicity bounded at the lower end by dichloromethane and the upper end by tributyl phosphate, and with anions that do not meet the stringent requirements of weak basicity, low polarizability of high + chemical stability, lower symmetry species are formed. -
Ch 17A Acid-Base Practice Problems
1 General Chemistry II Jasperse Acid-Base Chemistry. Extra Practice Problems General Types/Groups of problems: Conceptual Questions. Acids, Bases, and p1 Kb and pKb, Base Strength, and using Kb or p7-10 - + Conjugates, Miscellaneous pKb to Calculate [OH ], pOH, pH, and/or [H ] Recognizing Strong versus Weak Acids; p3 Recognizing Acid/Base Properties when p11 Recognizing Basic versus Nonbasic Ionics are Dissolved in Water pH Calculations; Relationships between pH and pOH p4 Answers p12 Ka: Sense + Calculations. Using Ka or pKa to Calculate p5 + [H ] and/or pH; using pH to calculate Ka or pKa Conceptual Questions. Acids, Bases, and Conjugates, Miscellaneous 1. In the Brønsted–Lowry definition of acids and bases, an acid __________ a. is a proton donor. d. breaks stable hydrogen bonds. b. is a proton acceptor. e. corrodes metals. c. forms stable hydrogen bonds. 2. In the Brønsted–Lowry definition of acids and bases, a base __________ a. is a proton donor. d. breaks stable hydrogen bonds. b. is a proton acceptor. e. corrodes metals. c. forms stable hydrogen bonds. 3. In the following reaction in aqueous solution, the acid reactant is __________ and its conjugate base product is __________. – + CH3COOH + NH3 CH3COO + NH4 – + a. CH3COOH; CH3COO d. NH3; NH4 + + b. CH3COOH; NH4 e. CH3COOH; H3O – c. NH3; CH3COO 4. In the following reaction in aqueous solution, the acid reactant is __________, and its conjugate base product is __________. – + 2– CH3NH2 + HSO4 CH3NH3 + SO4 + – 2– a. CH3NH2; CH3NH3 d. HSO4 ; SO4 2– – b. CH3NH2; SO4 e. HSO4 ; H3O+ – + c. HSO4 ; CH3NH3 2– 5. Which of the following is the conjugate acid of the hydrogen phosphate ion, HPO4 ? 3– a. -
Nacl + H2SO4 Nahso 4 +
SODIUM HYDROGEN SULFATE Chemical and Technical Assessment (CTA) Prepared by Madduri V. Rao, Ph.D. 1. Summary At the seventy-first meeting of JECFA, the Committee evaluated the safety, dietary intake and revision of specifications of sodium hydrogen sulfate (NaHSO4) at the request of the Codex Committee on Food Additives for its use as an acidifier. The Committee, at its sixty-eighth meeting (FAO/WHO, 2007), established specifications for sodium hydrogen sulfate for use in the preparation of acidified sodium chlorite, an antimicrobial washing solution. Sodium hydrogen sulfate, when added to food products containing water, ionizes to sodium ions, hydrogen ions, and sulfate ions. Since Acceptable Daily Intakes (ADIs) have been previously established for these ions, sodium hydrogen sulfate was not evaluated at the sixty-eighth meeting of the Committee. This document summarizes chemical and technical information on sodium hydrogen sulfate, partly based on information submitted by Jones- Hamilton Co.1. 2. Description Sodium hydrogen sulfate (NaHSO4, CAS No. 7681-38-1) is a colourless crystalline compound which is freely soluble in water. Sodium hydrogen sulfate, when added to food products containing water, ionizes to sodium ions, hydrogen ions, and sulfate ions. In addition to its use as an acidifier in foods (including its use in the preparation of acidified sodium chlorite), it also is used as an acidifier in pet foods, for pH control in swimming pools and SPAs, for ammonia control in livestock operations, and as an acid-type cleaner for commercial purposes. 3. Methods of Manufacture Sodium chloride and sulfuric acid are the starting materials in the manufacture of sodium hydrogen sulfate. -
Secondary Sulfate Minerals Associated with Acid Drainage in the Eastern US: Recycling of Metals and Acidity in Surficial Environments
University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln Geochemistry of Sulfate Minerals: A Tribute to Robert O. Rye US Geological Survey 2005 Secondary sulfate minerals associated with acid drainage in the eastern US: recycling of metals and acidity in surficial environments J.M. Hammarstrom U.S. Geological Survey R.R. Seal II U.S. Geological Survey A.L. Meier U.S. Geological Survey J.M. Kornfeld Dartmouth College Follow this and additional works at: https://digitalcommons.unl.edu/usgsrye Part of the Geochemistry Commons Hammarstrom, J.M.; Seal, R.R. II; Meier, A.L.; and Kornfeld, J.M., "Secondary sulfate minerals associated with acid drainage in the eastern US: recycling of metals and acidity in surficial environments" (2005). Geochemistry of Sulfate Minerals: A Tribute to Robert O. Rye. 2. https://digitalcommons.unl.edu/usgsrye/2 This Article is brought to you for free and open access by the US Geological Survey at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in Geochemistry of Sulfate Minerals: A Tribute to Robert O. Rye by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. Chemical Geology 215 (2005) 407–431 www.elsevier.com/locate/chemgeo Secondary sulfate minerals associated with acid drainage in the eastern US: recycling of metals and acidity in surficial environments J.M. Hammarstroma,*, R.R. Seal IIa, A.L. Meierb, J.M. Kornfeldc aU.S. Geological Survey, 954 National Center, Reston, Virginia 20192, USA bU.S. Geological Survey, 973 Denver Federal Center, Denver, Colorado 80225, USA cDartmouth College, Dartmouth, New Hampshire, USA Accepted 1 June 2004 Abstract Weathering of metal-sulfide minerals produces suites of variably soluble efflorescent sulfate salts at a number of localities in the eastern United States.