GRADES 6-12 DISTANCE LEARNING School Name Aledo High School
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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. -
A Study of Hydrogen Exchange in Benzene And
A STUDY OF HYDROGEN EXCHANGE IN BENZENE AND SEVERAL ALKYLBENZENES By REX LYNN ELMORE B~chelor of Arts Austin College Sherman, Texas 1960 Submitted to the faculty of the Graduate School of the Oklahpma State University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY August, 1965 J OKLAHOMA Jjf STATE UNIVERSITY .;.;, i' LIBRARY f DEC 6 1965 j' A STUDY OF HYDROGEN EXCHANGE IN BENZE~ AND ,,:.-· ;" . ·..... : SEVERAL ALKYLBENZENES f ~~~~~~~"'~"''""i;·~l'J!'~~ Thesis Approved: 593417 ii .ACKNOWLEDGMENTS Grateful acknowledgment is made to-Dr. E. M. Hodnett, research adviser, for his patience, guidance, and assistance throughout this work; to Dr. O. C. Dermer, head of the Chemistry Department, for his reading of the manuscript prior to its being typed; to Mr. C.R. Williams, formerly in the Chemistry Department, for his assistance in the early phases of the computer programming; to Mr. Preston Gant, Central Research Division of the Continental Oil Company, for helpful suggestions on the tritium assays; and to Mr. Prem S. Juneja for his helpful suggestions concerning experimental details which arose from time to time. Acknowledgment is made of financial assistance in the form of a graduate teaching assistantship in the Chemis.try Department. Also, a research as.sistantship from the Atomic Energy Commission, Contract No. AT(ll-1)-1049, through the Research Foundation is appreciated. Research done during the term of the latter assistantship provided material for this thesis. iii TABLE OF CONTENTS Chapter Page I. INTRODUCTION. 1 II. HISTORICAL, , 3 III. INTRODUCTION TO THE EXPERIMENTAL WORK 14 Objectives and Plan of the Study. -
Answer Key Chapter 16: Standard Review Worksheet – + 1
Answer Key Chapter 16: Standard Review Worksheet – + 1. H3PO4(aq) + H2O(l) H2PO4 (aq) + H3O (aq) + + NH4 (aq) + H2O(l) NH3(aq) + H3O (aq) 2. When we say that acetic acid is a weak acid, we can take either of two points of view. Usually we say that acetic acid is a weak acid because it doesn’t ionize very much when dissolved in water. We say that not very many acetic acid molecules dissociate. However, we can describe this situation from another point of view. We could say that the reason acetic acid doesn’t dissociate much when we dissolve it in water is because the acetate ion (the conjugate base of acetic acid) is extremely effective at holding onto protons and specifically is better at holding onto protons than water is in attracting them. + – HC2H3O2 + H2O H3O + C2H3O2 Now what would happen if we had a source of free acetate ions (for example, sodium acetate) and placed them into water? Since acetate ion is better at attracting protons than is water, the acetate ions would pull protons out of water molecules, leaving hydroxide ions. That is, – – C2H3O2 + H2O HC2H3O2 + OH Since an increase in hydroxide ion concentration would take place in the solution, the solution would be basic. Because acetic acid is a weak acid, the acetate ion is a base in aqueous solution. – – 3. Since HCl, HNO3, and HClO4 are all strong acids, we know that their anions (Cl , NO3 , – and ClO4 ) must be very weak bases and that solutions of the sodium salts of these anions would not be basic. -
Acids Lewis Acids and Bases Lewis Acids Lewis Acids: H+ Cu2+ Al3+ Lewis Bases
E5 Lewis Acids and Bases (Session 1) Acids November 5 - 11 Session one Bronsted: Acids are proton donors. • Pre-lab (p.151) due • Problem • 1st hour discussion of E4 • Compounds containing cations other than • Lab (Parts 1and 2A) H+ are acids! Session two DEMO • Lab: Parts 2B, 3 and 4 Problem: Some acids do not contain protons Lewis Acids and Bases Example: Al3+ (aq) = ≈ pH 3! Defines acid/base without using the word proton: + H H H • Cl-H + • O Cl- • • •• O H H Acid Base Base Acid . A BASE DONATES unbonded ELECTRON PAIR/S. An ACID ACCEPTS ELECTRON PAIR/S . Deodorants and acid loving plant foods contain aluminum salts Lewis Acids Lewis Bases . Electron rich species; electron pair donors. Electron deficient species ; potential electron pair acceptors. Lewis acids: H+ Cu2+ Al3+ “I’m deficient!” Ammonia hydroxide ion water__ (ammine) (hydroxo) (aquo) Acid 1 Lewis Acid-Base Reactions Lewis Acid-Base Reactions Example Metal ion + BONDED H H H + • to water H + • O O • • •• molecules H H Metal ion Acid + Base Complex ion surrounded by water . The acid reacts with the base by bonding to one molecules or more available electron pairs on the base. The acid-base bond is coordinate covalent. The product is a complex or complex ion Lewis Acid-Base Reaction Products Lewis Acid-Base Reaction Products Net Reaction Examples Net Reaction Examples 2+ 2+ + + Pb + 4 H2O [Pb(H2O)4] H + H2O [H(H2O)] Lewis acid Lewis base Tetra aquo lead ion Lewis acid Lewis base Hydronium ion 2+ 2+ 2+ 2+ Ni + 6 H2O [Ni(H2O)6] Cu + 4 H2O [Cu(H2O)4] Lewis acid Lewis base Hexa aquo nickel ion Lewis acid Lewis base Tetra aquo copper(II)ion DEMO DEMO Metal Aquo Complex Ions Part 1. -
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. -
Lesson 21: Acids & Bases
Lesson 21: Acids & Bases - Far From Basic Lesson Objectives: • Students will identify acids and bases by the Lewis, Bronsted-Lowry, and Arrhenius models. • Students will calculate the pH of given solutions. Getting Curious You’ve probably heard of pH before. Many personal hygiene products make claims about pH that are sometimes based on true science, but frequently are not. pH is the measurement of [H+] ion concentration in any solution. Generally, it can tell us about the acidity or alkaline (basicness) of a solution. Click on the CK-12 PLIX Interactive below for an introduction to acids, bases, and pH, and then answer the questions below. Directions: Log into CK-12 as follows: Username - your Whitmore School Username Password - whitmore2018 Questions: Copy and paste questions 1-3 in the Submit Box at the bottom of this page, and answer the questions before going any further in the lesson: 1. After dragging the small white circles (in this simulation, the indicator papers) onto each substance, what do you observe about the pH of each substance? 2. If you were to taste each substance (highly inadvisable in the chemistry laboratory!), how would you imagine they would taste? 3. Of the three substances, which would you characterize as acid? Which as basic? Which as neutral? Use the observed pH levels to support your hypotheses. Chemistry Time Properties of Acids and Bases Acids and bases are versatile and useful materials in many chemical reactions. Some properties that are common to aqueous solutions of acids and bases are listed in the table below. Acids Bases conduct electricity in solution conduct electricity in solution turn blue litmus paper red turn red litmus paper blue have a sour taste have a slippery feeling react with acids to create a neutral react with bases to create a neutral solution solution react with active metals to produce hydrogen gas Note: Litmus paper is a type of treated paper that changes color based on the acidity of the solution it comes in contact with. -
Acids and Bases
self study Most of this is probably background from a prior chemistry course; some near the end is GG325 review Aqueous Inorganic Geochemistry of Natural Waters Three important topics: 1. Acids, bases and the aqueous CO 2 system 2. Behavior of ions in aqueous solution 3. Quantifying aqueous solubility and total dissolved solids (TDS) Pease read Manahan chapter 3 and review chapter 28 (6 th Ed) for next week GG425 Wk2, S2016 Acids and Bases GG425 Wk2, S2016 1 1. Two Types of Acids and Bases: a. Brönstead acids and bases contain H + and OH - HCl ↔ H + + + Cl- (acid) NaOH ↔ Na + + OH - (base). + - water is acid and base simultaneously, H 2O ↔ H + OH . pure water and acid neutral aqueous solutions have equal amounts of H + and OH -. b. Lewis acids and bases Brönstead acids can be thought of as electron deficient ions and bases as electron excessive ions , which provides a different perspective on acidity/basisity that we can extend to other (non protic and non hydroxyl) compounds. We call this the Lewis acid/base concept. GG425 Wk2, S2016 Brönstead acidity: Kw is the equilibrium constant for the dissociation of water. + - H2O ↔ H + OH + - -14 Kw = [H ][OH ] = 10 at 25 EC Kw has a slight temperature dependence: Temp ( EC) Kw 0 10 -14.94 less dissociated 25 10 -14 60 10 -13.02 more dissociated GG425 Wk2, S2016 2 Brönstead acidity: + - H2O ↔ H + OH + - Kw = [H ][OH ] An acid neutral solution always has [H +] = [OH -]. Setting [H +] = x, yields x 2= 10 -14 x = 10 -7 = moles of H + in this solution. -
Protonation and Chloroplast Membrane Structure
PROTONATION AND CHLOROPLAST MEMBRANE STRUCTURE SATORU MURAKAMI and LESTER PACKER From the Department of Physiology-Anatomy, University of California, Berkeley, California 94720 Downloaded from http://rupress.org/jcb/article-pdf/47/2/332/1069424/332.pdf by guest on 29 September 2021 ABSTRACT Light changes the structure of chloroplasts . This effect was investigated by high resolution electron microscopy, photometric methods, and chemical modification . (a) A reversible contraction of chloroplast membrane occurs upon illumination, dark titration with H+, or increasing osmolarity . These gross structural changes arise from a flattening of the thylakoids, with a corresponding decrease in the spacing between membranes . Microdensitometry showed that illumination or dark addition of H+ resulted in a 13-23% decrease in mem- brane thickness. Osmotically contracted chloroplasts do not show this effect . (b) Rapid glutaraldehyde fixation during actual experiments revealed that transmission changes are closely correlated with the spacing changes and therefore reflect an osmotic mechanism, whereas the light scattering changes have kinetics most similar to changes in membrane thickness or conformation . (c) Kinetic analysis of light scattering and transmission changes with the changes in fluorescence of anilinonaphthalene sulfonic acid bound to membranes revealed that fluorescence preceded light scattering or transmission changes. (d) It is concluded that the temporal sequence of events following illumination probably are proto- nation, changes in the environment within the membrane, change in membrane thickness, change in internal osmolarity accompanying ion movements with consequent collapse and flattening of thylakoid, change in the gross morphology of the inner chloroplast membrane system, and change in the gross morphology of whole chloroplasts . INTRODUCTION Ample evidence has been brought forward in changes in chloroplast membranes is still undeter- recent years to demonstrate, both in vitro (1-9) mined . -
General Chemistry/Properties and Theories of Acids and Bases 1 General Chemistry/Properties and Theories of Acids and Bases
General Chemistry/Properties and Theories of Acids and Bases 1 General Chemistry/Properties and Theories of Acids and Bases Acid-Base Reaction Theories Acids and bases are everywhere. Some foods contain acid, like the citric acid in lemons and the lactic acid in dairy. Cleaning products like bleach and ammonia are bases. Chemicals that are acidic or basic are an important part of chemistry. Helpful Hint! You may need to refresh your memory on naming acids. Several different theories explain what composes an acid and a base. The first scientific definition of an acid was proposed by the French chemist Antoine Lavoisier in the eighteenth century. He proposed that acids contained oxygen, although he did not know the dual composition of acids such as hydrochloric acid (HCl). Over the years, much more accurate definitions of acids and bases have been created. Arrhenius Theory The Swedish chemist Svante Arrhenius published his theory of acids and bases in 1887. It can be simply explained by these two points: Arrhenius Acids and Bases 1. An acid is a substance which dissociates in water to produce one or more hydrogen ions (H+). 2. A base is a substance which dissociates in water to produce one or more hydroxide ions (OH-). Based on this definition, you can see that Arrhenius acids must be soluble in water. Arrhenius acid-base reactions can be summarized with three generic equations: Svante Arrhenius General Chemistry/Properties and Theories of Acids and Bases 2 An acid will dissociate in water producing hydrogen ions. A base (usually containing a metal) will dissociate in water to product hydroxide ions. -
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. -
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 .