| Journal Articles: 12 results |
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Unified Approximations: A New Approach for Monoprotic Weak Acid–Base Equilibria Harry L. Pardue, Ihab N. Odeh, and Teweldemedhin M. Tesfai This article describes a new approach to approximate calculations for monoprotic acidbase equilibria in otherwise pure water. The new approach, identified herein as unified approximations, uses a simple decision criterion to select between situations that should be treated as deprotonation and protonation reactions. The remaining treatment takes account of changes in concentrations of conjugate acidbase pairs for all situations and ignores autoprotolysis only for situations for which the analytical concentration of either the conjugate acid or conjugate base will always be larger than zero. Pardue, Harry L.; Odeh, Ihab N.; Tesfai, Teweldemedhin M. J. Chem. Educ. 2004, 81, 1367.
Acids / Bases |
Equilibrium |
Chemometrics
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Acid–Base Titrations in Nonaqueous Solvents and Solvent Mixtures Lajos Barcza and Ágnes Buvári-Barcza Discussion of acid-base theory, the role of hydrogen bonding in acid-base reactions, and promoting, leveling, and differentiating effects. Barcza, Lajos; Buvári-Barcza, Ágnes. J. Chem. Educ. 2003, 80, 822.
Acids / Bases |
Equilibrium |
Solutions / Solvents |
Titration / Volumetric Analysis |
Enrichment / Review Materials |
Hydrogen Bonding |
Lewis Acids / Bases |
Brønsted-Lowry Acids / Bases
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Chemical Equilibria Involving Copper(II) Ethylenediamine Complexes Roberto Zingales Demonstration illustrating the formation of two different complexes when copper(II) ions react with ethylenediamine. Zingales, Roberto. J. Chem. Educ. 2003, 80, 535.
Equilibrium |
Aqueous Solution Chemistry |
Reactions |
Amines / Ammonium Compounds |
Precipitation / Solubility
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Evaluating Solubility of Sparingly Soluble Diprotic Acid Salts Jean M. Nigretto The use of logarithmic concentration diagrams as a convenient tool for finding approximate solutions to the pH of solutions containing sparingly soluble diprotic acid salts in pure water; an application of this method based on a series of carbonate salts is presented. Nigretto, Jean M. J. Chem. Educ. 2001, 78, 631.
Acids / Bases |
Aqueous Solution Chemistry |
Equilibrium |
Solutions / Solvents |
Precipitation / Solubility |
pH
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Spreadsheet Techniques for Evaluating the Solubility of Sparingly Soluble Salts of Weak Acids José L. Guinón, José García-Antón, and Valentín Pérez-Herranz A spreadsheet of Microsoft Excel for determining the solubility of sparingly soluble salts is described. The chart and worksheet are shown simultaneously on the screen. The worksheet can be used for any salt by merely changing the data for the solubility product constant and ionization constants. Guinn, Jos L.; Garca-Antn, Jos; Prez-Herranz, Valentn. J. Chem. Educ. 1999, 76, 1157.
Computational Chemistry |
Equilibrium |
Laboratory Computing / Interfacing |
Quantitative Analysis |
Acids / Bases |
Precipitation / Solubility
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Predicting Acid-Base Titration Curves without Calculations Dennis W. Barnum In this paper a qualitative and systematic method for sketching titration curves is presented. Even the more complex cases such as salts or polyprotic acids and bases are treated just as easily as simple monoprotic acids. Having students predict the shape of titration curves from known equilibrium constants helps to focus attention on the general principles without distraction by the mathematics. Barnum, Dennis W. J. Chem. Educ. 1999, 76, 938.
Acids / Bases |
Quantitative Analysis |
Water / Water Chemistry |
Equilibrium |
Learning Theories |
Titration / Volumetric Analysis |
Chemometrics
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The Fizz Keeper, a Case Study in Chemical Education, Equilibrium, and Kinetics Reed Howald The chemistry of the loss of carbonation from carbonated beverages on storage is considered. Increasing the pressure of CO2(g) will restore carbonation, but an increase in pressure adding air should not affect the equilibria. It can and does, however, affect the kinetics-the rate at which a new equilibrium is established. Thus the Fizz Keeper is effective for storage of resealed pop containers for hours, but not for periods of weeks or months. Howald, Reed. J. Chem. Educ. 1999, 76, 208.
Transport Properties |
Equilibrium |
Gases |
Kinetics |
Aqueous Solution Chemistry |
Consumer Chemistry |
Applications of Chemistry
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Ionization or Dissociation? Emeric Schultz The use of the terms Dissociation and Ionization in the teaching of chemistry is discussed. It is suggested that the term dissociation, and what it suggests in terms of ordinary language, is inappropriate when used in certain contexts. Since an alternate and more physically correct term, specifically ionization, is available for these contexts, it is argued that this term be used consistently in these contexts. Schultz, Emeric. J. Chem. Educ. 1997, 74, 868.
Equilibrium |
Nomenclature / Units / Symbols
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The acid equilibrium constant is unity! (the author replies) Thompson, Ralph J. The interpretation of thermodynamic equilibrium constants by Baldwin and Burchill is quite proper and technically correct. Thompson, Ralph J. J. Chem. Educ. 1992, 69, 515.
Acids / Bases |
Equilibrium |
Aqueous Solution Chemistry
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The extent of acid-base reactions Thompson, Ralph J. How to calculate the equilibrium constant of an acid-base reaction. Thompson, Ralph J. J. Chem. Educ. 1990, 67, 220.
Acids / Bases |
Reactions |
Equilibrium
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Teaching ionic equilibrium: Use of log chart transparencies Freiser, Henry; Fernando, Quintus The use of graphical methods brings the problem of significance of various terms in complicated expressions into proper focus. Furthermore, a pictorial representation permits the student to see at a glance how the concentrations of various species in a system at equilibrium change with conditions. Freiser, Henry; Fernando, Quintus J. Chem. Educ. 1965, 42, 35.
Aqueous Solution Chemistry |
Equilibrium |
Acids / Bases |
pH |
Chemometrics |
Brønsted-Lowry Acids / Bases
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The algebra of simultaneous equilibria Davidson, David; Geller, Kenneth Presents a series of rules for dealing with simultaneous equilibria using simple algebra. Davidson, David; Geller, Kenneth J. Chem. Educ. 1953, 30, 238.
Equilibrium |
Chemometrics |
Acids / Bases |
Aqueous Solution Chemistry |
Oxidation / Reduction
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