Appendix a List of Acronyms, Abbreviations, and Symbols
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Glossary Physics (I-Introduction)
1 Glossary Physics (I-introduction) - Efficiency: The percent of the work put into a machine that is converted into useful work output; = work done / energy used [-]. = eta In machines: The work output of any machine cannot exceed the work input (<=100%); in an ideal machine, where no energy is transformed into heat: work(input) = work(output), =100%. Energy: The property of a system that enables it to do work. Conservation o. E.: Energy cannot be created or destroyed; it may be transformed from one form into another, but the total amount of energy never changes. Equilibrium: The state of an object when not acted upon by a net force or net torque; an object in equilibrium may be at rest or moving at uniform velocity - not accelerating. Mechanical E.: The state of an object or system of objects for which any impressed forces cancels to zero and no acceleration occurs. Dynamic E.: Object is moving without experiencing acceleration. Static E.: Object is at rest.F Force: The influence that can cause an object to be accelerated or retarded; is always in the direction of the net force, hence a vector quantity; the four elementary forces are: Electromagnetic F.: Is an attraction or repulsion G, gravit. const.6.672E-11[Nm2/kg2] between electric charges: d, distance [m] 2 2 2 2 F = 1/(40) (q1q2/d ) [(CC/m )(Nm /C )] = [N] m,M, mass [kg] Gravitational F.: Is a mutual attraction between all masses: q, charge [As] [C] 2 2 2 2 F = GmM/d [Nm /kg kg 1/m ] = [N] 0, dielectric constant Strong F.: (nuclear force) Acts within the nuclei of atoms: 8.854E-12 [C2/Nm2] [F/m] 2 2 2 2 2 F = 1/(40) (e /d ) [(CC/m )(Nm /C )] = [N] , 3.14 [-] Weak F.: Manifests itself in special reactions among elementary e, 1.60210 E-19 [As] [C] particles, such as the reaction that occur in radioactive decay. -
Types of Chemical Reactions and Solution Stoichiometry
Types of Chemical Reactions 4 and Solution Stoichiometry Contents 4.1 Water, the Common Solvent 4.2 The Nature of Aqueous Solutions: Strong and Weak Electrolytes • Strong Electrolytes • Weak Electrolytes • Nonelectrolytes 4.3 The Composition of Solutions • Dilution 4.4 Types of Chemical Reactions 4.5 Precipitation Reactions 4.6 Describing Reactions in Solution 4.7 Stoichiometry of Precipitation Reactions 4.8 Acid–Base Reactions • Acid–Base Titrations 4.9 Oxidation–Reduction Reactions • Oxidation States • The Characteristics of Oxidation–Reduction Reactions 4.10 Balancing Oxidation– Reduction Equations • The Half-Reaction Method for Balancing Oxidation–Reduction Reactions in Aqueous Solutions Yellow lead(II) iodide is produced when lead(II) nitrate is mixed with potassium iodide. 126 Much of the chemistry that affects each of us occurs among substances dissolved in water. For example, virtually all the chemistry that makes life possible occurs in an aqueous environment. Also, various medical tests involve aqueous reactions, depending heavily on analyses of blood and other body fluids. In addition to the common tests for sugar, cholesterol, and iron, analyses for specific chemical markers allow detection of many diseases before obvious symptoms occur. Aqueous chemistry is also important in our environment. In recent years, contami- nation of the groundwater by substances such as chloroform and nitrates has been widely publicized. Water is essential for life, and the maintenance of an ample supply of clean water is crucial to all civilization. To understand the chemistry that occurs in such diverse places as the human body, the atmosphere, the groundwater, the oceans, the local water treatment plant, your hair as you shampoo it, and so on, we must understand how substances dissolved in water react with each other. -
Chapter 12 Lecture Notes
Chemical Kinetics “The study of speeds of reactions and the nanoscale pathways or rearrangements by which atoms and molecules are transformed to products” Chapter 13: Chemical Kinetics: Rates of Reactions © 2008 Brooks/Cole 1 © 2008 Brooks/Cole 2 Reaction Rate Reaction Rate Combustion of Fe(s) powder: © 2008 Brooks/Cole 3 © 2008 Brooks/Cole 4 Reaction Rate Reaction Rate + Change in [reactant] or [product] per unit time. Average rate of the Cv reaction can be calculated: Time, t [Cv+] Average rate + Cresol violet (Cv ; a dye) decomposes in NaOH(aq): (s) (mol / L) (mol L-1 s-1) 0.0 5.000 x 10-5 13.2 x 10-7 10.0 3.680 x 10-5 9.70 x 10-7 20.0 2.710 x 10-5 7.20 x 10-7 30.0 1.990 x 10-5 5.30 x 10-7 40.0 1.460 x 10-5 3.82 x 10-7 + - 50.0 1.078 x 10-5 Cv (aq) + OH (aq) → CvOH(aq) 2.85 x 10-7 60.0 0.793 x 10-5 -7 + + -5 1.82 x 10 change in concentration of Cv Δ [Cv ] 80.0 0.429 x 10 rate = = 0.99 x 10-7 elapsed time Δt 100.0 0.232 x 10-5 © 2008 Brooks/Cole 5 © 2008 Brooks/Cole 6 1 Reaction Rates and Stoichiometry Reaction Rates and Stoichiometry Cv+(aq) + OH-(aq) → CvOH(aq) For any general reaction: a A + b B c C + d D Stoichiometry: The overall rate of reaction is: Loss of 1 Cv+ → Gain of 1 CvOH Rate of Cv+ loss = Rate of CvOH gain 1 Δ[A] 1 Δ[B] 1 Δ[C] 1 Δ[D] Rate = − = − = + = + Another example: a Δt b Δt c Δt d Δt 2 N2O5(g) 4 NO2(g) + O2(g) Reactants decrease with time. -
Chapter 17: Electrochemistry
4/12/2021 17.1 Electrochemistry Chapter 17: Deals with chemical reactions that produce electricity and the changes associated Electrochemistry with the passage of charge through matter. Reactions involve electron transfer – oxidation/reduction (redox) Example: A typical AA alkaline battery is rated at 1.5 V. This means the electrical potential difference between the +/– terminals is 1.5 V. It is the chemical reactions in the battery that give rise to this difference. 1 2 1 2 Redox Recap Assigning oxidation numbers Oxidation number rules: 1.) Ox. # = 0 for an atom in pure, elemental state 2+ 2.) Ox. # = <charge> for monatomic ion: Ox. # = 2 for Ca Oxidation number: +1 –1 3.) Sum of all Ox. #’s for atoms in polyatomic ion = charge on polyatomic ion Total contribution to charge: +2 –2 = 0 4.) Sum of all Ox. #’s = charge on species: H2O Ox.(H) = 1, Ox(O) = –2 Oxidation number: +1 +6 –2 Total contribution to charge: +2 +6 –8 = 0 3 4 3 4 1 4/12/2021 Redox terminology Redox terminology applied Oxidation – the loss of electrons OIL RIG – “oxidation is losing, Reduction – the gain of electrons reduction is gaining” 0 +2 –1 +2 –1 0 “Substance X undergoes oxidation.” – X lost electrons 0 +2 –2 +2 –2 0 “Substance Y was reduced.” – Y gained electrons Oxidizing agent – the species that undergoes reduction What was oxidized? Zn Oxidizing agent = CuCl2 Reducing agent – the species that undergoes oxidation What was reduced? Cu2+ Reducing agent = Zn “Substance Z is the oxidizing agent.” – Z gains electrons What is the spectator ion? Cl– (Think: Travel agent – allows someone else to travel) 5 6 5 6 17.1 Balancing redox reactions Example: Balancing redox reaction in acidic solution 1.) Assign oxidation states to all atoms. -
Free Radical Reactions (Read Chapter 4) A
Chemistry 5.12 Spri ng 2003, Week 3 / Day 2 Handout #7: Lecture 11 Outline IX. Free Radical Reactions (Read Chapter 4) A. Chlorination of Methane (4-2) 1. Mechanism (4-3) B. Review of Thermodynamics (4-4,5) C. Review of Kinetics (4-8,9) D. Reaction-Energy Diagrams (4-10) 1. Thermodynamic Control 2. Kinetic Control 3. Hammond Postulate (4-14) 4. Multi-Step Reactions (4-11) 5. Chlorination of Methane (4-7) Suggested Problems: 4-35–37,40,43 IX. A. Radical Chlorination of Methane H heat (D) or H H C H Cl Cl H C Cl H Cl H light (hv) H H Cl Cl D or hv D or hv etc. H C Cl H C Cl H Cl Cl C Cl H Cl Cl Cl Cl Cl H H H • Why is light or heat necessary? • How fast does it go? • Does it give off or consume heat? • How fast are each of the successive reactions? • Can you control the product ratio? To answer these questions, we need to: 1. Understand the mechanism of the reaction (arrow-pushing!). 2. Use thermodynamics and kinetics to analyze the reaction. 1 1. Mechanism of Radical Chlorination of Methane (Free-Radical Chain Reaction) Free-radical chain reactions have three distinct mechanistic steps: • initiation step: generates reactive intermediate • propagation steps: reactive intermediates react with stable molecules to generate other reactive intermediates (allows chain to continue) • termination step: side-reactions that slow the reaction; usually combination of two reactive intermediates into one stable molecule Initiation Step: Cl2 absorbs energy and the bond is homolytically cleaved. -
Andrea Deoudes, Kinetics: a Clock Reaction
A Kinetics Experiment The Rate of a Chemical Reaction: A Clock Reaction Andrea Deoudes February 2, 2010 Introduction: The rates of chemical reactions and the ability to control those rates are crucial aspects of life. Chemical kinetics is the study of the rates at which chemical reactions occur, the factors that affect the speed of reactions, and the mechanisms by which reactions proceed. The reaction rate depends on the reactants, the concentrations of the reactants, the temperature at which the reaction takes place, and any catalysts or inhibitors that affect the reaction. If a chemical reaction has a fast rate, a large portion of the molecules react to form products in a given time period. If a chemical reaction has a slow rate, a small portion of molecules react to form products in a given time period. This experiment studied the kinetics of a reaction between an iodide ion (I-1) and a -2 -1 -2 -2 peroxydisulfate ion (S2O8 ) in the first reaction: 2I + S2O8 I2 + 2SO4 . This is a relatively slow reaction. The reaction rate is dependent on the concentrations of the reactants, following -1 m -2 n the rate law: Rate = k[I ] [S2O8 ] . In order to study the kinetics of this reaction, or any reaction, there must be an experimental way to measure the concentration of at least one of the reactants or products as a function of time. -2 -2 -1 This was done in this experiment using a second reaction, 2S2O3 + I2 S4O6 + 2I , which occurred simultaneously with the reaction under investigation. Adding starch to the mixture -2 allowed the S2O3 of the second reaction to act as a built in “clock;” the mixture turned blue -2 -2 when all of the S2O3 had been consumed. -
2 Amount and Concentration: Making and Diluting Solutions 2 Amount and Concentration; Making and Diluting Solutions
Essential Maths for Medics and Vets Reference Materials Module 2. Amount and Concentration. 2 Amount and concentration: making and diluting solutions 2 Amount and concentration; making and diluting solutions.........................................................1 2A Rationale.............................................................................................................................1 2B Distinguishing between amount and concentration, g and %w/v..........................................1 2C Distinguishing between amount and concentration, moles and molar...................................2 2D Practice converting g/L to M and vice versa........................................................................3 2E Diluting Solutions ...............................................................................................................5 2F Practice calculating dilutions ...............................................................................................6 Summary of learning objectives................................................................................................7 2A Rationale Biological and biochemical investigations rely completely upon being able to detect the concentration of a variety of substances. For example, in diabetics it is important to know the concentration of glucose in the blood and you may also need to be able to calculate how much insulin would need to be dissolved in a certain volume of saline so as to give the right amount in a 1ml injection volume. It is also vitally -
Determination of the Molar Mass of an Unknown Solid by Freezing Point Depression
Determination of the Molar Mass of an Unknown Solid by Freezing Point Depression GOAL AND OVERVIEW In the first part of the lab, a series of solutions will be made in order to determine the freezing point depression constant, Kf, for cyclohexane. The freezing points of these solutions, which will contain known amounts of p-dichlorobenzene dissolved in cyclohexane, will be measured. In the second part of the lab, the freezing point of a cyclohexane solution will be prepared that contains a known mass of an unknown organic solid. The measured freezing point change will be used to calculate the molar mass of the unknown solid. Objectives and Science Skills • Understand and explain colligative properties of solutions, including freezing point depression. • Measure the freezing point of a pure solvent and of a solution in that solvent containing an unknown solute. • Calculate the molar mass of the unknown solute and determine its probable identity from a set of choices. • Quantify the expected freezing point change in a solution of known molality. • Quantitatively and qualitatively compare experimental results with theoretical values. • Identify and discuss factors or effects that may contribute to the uncertainties in values determined from experimental data. SUGGESTED REVIEW AND EXTERNAL READING • Reference information on thermodynamics; data analysis; relevant textbook information BACKGROUND If a liquid is at a higher temperature than its surroundings, the liquid's temperature will fall as it gives up heat to the surroundings. When the liquid's temperature reaches its freezing point, the liquid's temperature will not fall as it continues to give up heat to the surroundings. -
Chapter 20 Electrochemistry
Chapter 20 Electrochemistry Learning goals and key skills: Identify oxidation, reduction, oxidizing agent, and reducing agent in a chemical equation Complete and balance redox equations using the method of half-reactions. Sketch a voltaic cell and identify its cathode, anode, and the directions in which electrons and ions move. o Calculate standard emfs (cell potentials), E cell, from standard reduction potentials. Use reduction potentials to predict whether a redox reaction is spontaneous. o o Relate E cell to DG and equilibrium constants. Calculate emf under nonstandard conditions. Identify the components of common batteries. Describe the construction of a lithium-ion battery and explain how it works. Describe the construction of a fuel cell and explain how it generates electrical energy. Explain how corrosion occurs and how it is prevented by cathodic protection. Describe the reactions in electrolytic cells. Relate the amounts of products and reactants in redox reactions to electrical charge. Electrochemistry Electrochemistry is the study of the relationships between electricity and chemical reactions. • It includes the study of both spontaneous and nonspontaneous processes. 1 Redox reactions: assigning oxidation numbers Oxidation numbers help keep track of what species loses electrons and what species gains them. • An element is oxidized when the oxidation number increases • An element is reduced when the oxidation number decreases • an oxidizing agent causes another element to be oxidized • a reducing agent causes another element to be reduced. Assigning oxidation numbers (sect. 4.4) 1. Elemental form, each atom has ox. # = 0. Zn O2 O3 I2 S8 P4 2. Simple ions, = charge on ion. -1 for Cl-, +2 for Mg2+ 3. -
Physical and Analytical Electrochemistry: the Fundamental
Electrochemical Systems The simplest and traditional electrochemical process occurring at the boundary between an electronically conducting phase (the electrode) and an ionically conducting phase (the electrolyte solution), is the heterogeneous electro-transfer step between the electrode and the electroactive species of interest present in the solution. An example is the plating of nickel. Ni2+ + 2e- → Ni Physical and Analytical The interface is where the action occurs but connected to that central event are various processes that can Electrochemistry: occur in parallel or series. Figure 2 demonstrates a more complex interface; it represents a molecular scale snapshot The Fundamental Core of an interface that exists in a fuel cell with a solid polymer (capable of conducting H+) as an electrolyte. of Electrochemistry However, there is more to an electrochemical system than a single by Tom Zawodzinski, Shelley Minteer, interface. An entire circuit must be made and Gessie Brisard for measurable current to flow. This circuit consists of the electrochemical cell plus external wiring and circuitry The common event for all electrochemical processes is that (power sources, measuring devices, of electron transfer between chemical species; or between an etc). The cell consists of (at least) electrode and a chemical species situated in the vicinity of the two electrodes separated by (at least) one electrolyte solution. Figure 3 is electrode, usually a pure metal or an alloy. The location where a schematic of a simple circuit. Each the electron transfer reactions take place is of fundamental electrode has an interface with a importance in electrochemistry because it regulates the solution. Electrons flow in the external behavior of most electrochemical systems. -
Guide for the Use of the International System of Units (SI)
Guide for the Use of the International System of Units (SI) m kg s cd SI mol K A NIST Special Publication 811 2008 Edition Ambler Thompson and Barry N. Taylor NIST Special Publication 811 2008 Edition Guide for the Use of the International System of Units (SI) Ambler Thompson Technology Services and Barry N. Taylor Physics Laboratory National Institute of Standards and Technology Gaithersburg, MD 20899 (Supersedes NIST Special Publication 811, 1995 Edition, April 1995) March 2008 U.S. Department of Commerce Carlos M. Gutierrez, Secretary National Institute of Standards and Technology James M. Turner, Acting Director National Institute of Standards and Technology Special Publication 811, 2008 Edition (Supersedes NIST Special Publication 811, April 1995 Edition) Natl. Inst. Stand. Technol. Spec. Publ. 811, 2008 Ed., 85 pages (March 2008; 2nd printing November 2008) CODEN: NSPUE3 Note on 2nd printing: This 2nd printing dated November 2008 of NIST SP811 corrects a number of minor typographical errors present in the 1st printing dated March 2008. Guide for the Use of the International System of Units (SI) Preface The International System of Units, universally abbreviated SI (from the French Le Système International d’Unités), is the modern metric system of measurement. Long the dominant measurement system used in science, the SI is becoming the dominant measurement system used in international commerce. The Omnibus Trade and Competitiveness Act of August 1988 [Public Law (PL) 100-418] changed the name of the National Bureau of Standards (NBS) to the National Institute of Standards and Technology (NIST) and gave to NIST the added task of helping U.S. -
Validation of the PATHOGENA Electron-Activated Reactor For
ineering ng & E P l r a o c i c e m s Opoku-Duah et al., J Chem Eng Process Technol 2015, 6:3 e s Journal of h T C e f c h o DOI: 10.4172/2157-7048.1000239 l ISSN: 2157-7048 n a o n l o r g u y o J Chemical Engineering & Process Technology CommentryResearch Article OpenOpen Access Access Validation of the PATHOGENA Electron-Activated Reactor for Purifying Contaminated Water in the Parkersburg Area in West Stephen Opoku-Duah*, Gordon Wells1, Wycliff Kipkomoi1, Ashley Wilcox1, Dennis Johnson2 and Mark Wiley3 1Ohio Valley University College of Arts and Sciences, Ohio Valley University, 1 Campus View Drive, Vienna, WV 26105 2EcH2O International Group, 14 Inverness Drive East, Suite D-112, Englewood, CO 80138 3TCG Global, 14104 E. Davies Ave., Suite B, Centennial, CO 80112 Abstract This paper concerns validation of the PATHOGENA version of electron-activated reactors designed to purify contaminated water to make it potable. The basic design of PATHOGENA is a 100-gallon plastic tank batch reactor which houses a vapor-ion plasma (VIP) generator and 1-micron ion-separator (ION-SEP) porous water filter. While the VIP generator splits ambient air into aggressive water treatment agents in the form of charged ions, free electrons, hydroxyl and peroxyl radicals using UV radiation, the ION-SEP filter is designed to eliminate broad-spectrum bacteria and other microbes. The validation process was started with creation of water quality database from: (a) contaminated surface water; (b) EPA/West Virginia Water Quality Standards, and (c) Vienna City Council drinking water.