| Journal Articles: 38 results |
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Imidazole as a pH Probe: An NMR Experiment for the General Chemistry Laboratory William J. Hagan, Jr., Dennis L. Edie, and Linda B. Cooley An experiment is described that employs the 1H-NMR signal of aqueous imidazole to determine the pH of an unknown solution. The procedure involves the preparation of a calibration curve, which is then used for the analysis of the unknown(s). Hagan, William J., Jr.; Edie, Dennis L.; Cooley, Linda B. J. Chem. Educ. 2007, 84, 1188.
Acids / Bases |
Aqueous Solution Chemistry |
Aromatic Compounds |
Calibration |
NMR Spectroscopy |
pH
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pH Paradoxes: Demonstrating That It Is Not True That pH ≡ -log[H+] Christopher G. McCarty and Ed Vitz Six demonstrations highlighting paradoxes that arise if pH is incorrectly defined as -log[H+] are presented as justification for the recommendation that pH should be correctly defined as pH = -log aH+ in textbooks. McCarty, Christopher G.; Vitz, Ed. J. Chem. Educ. 2006, 83, 752.
Acids / Bases |
Aqueous Solution Chemistry |
Ion Selective Electrodes |
pH |
Quantitative Analysis
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Using Visible Spectrophotometers and pH Measurements To Study Speciation in a Guided-Inquiry Laboratory William H. Otto, Cynthia K. Larive, Susan L. Mason, Janet B. Robinson, Joseph A. Heppert, and James D. Ellis A collective-effort, guided-inquiry laboratory investigation was developed for the second-semester general chemistry laboratory for the purpose of increasing student conceptual understanding of equilibrium and speciation phenomena. This investigation required students to employ the chemical indicator phenol red in phosphate buffer solution, computer interfaced pH probes, and visible spectrophotometers. Through a combination of potentiometric and visible absorption measurements, the students determined the pH conditions that alter equilibrium concentrations of multiple species (colored and transparent) in solution. Otto, William H.; Larive, Cynthia K.; Mason, Susan L.; Robinson, Janet B.; Heppert, Joseph A.; Ellis, James D. J. Chem. Educ. 2005, 82, 1552.
Acids / Bases |
UV-Vis Spectroscopy |
Equilibrium |
pH |
Water / Water Chemistry |
Dyes / Pigments
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Teaching pH Measurements with a Student-Assembled Combination Quinhydrone Electrode Fritz Scholz, Tim Steinhardt, Heike Kahlert, Jens R. Pörksen, and Jürgen Behnert A combination pH electrode that can be assembled by the student is described. It consists of a glass holder and two sensors in the form of rubber stoppers that contain quinhydrone and graphite. The combination electrode is suitable to teach potentiometric measurements, pH measurements, and the interplay of acidbase and redox equilibria. The electrode meets highest safety standards and overcomes the troubles associated with the use of the conventional quinhydrone electrode. Scholz, Fritz; Steinhardt, Tim; Kahlert, Heike; Pörksen, Jens R.; Behnert, Jürgen. J. Chem. Educ. 2005, 82, 782.
Acids / Bases |
pH |
Laboratory Equipment / Apparatus |
Electrochemistry
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From Christmas Ornament to Glass Electrode Rogério T. da Rocha, Ivano G. R. Gutz, and Claudimir L. do Lago Instructions and use of a homemade glass electrode for pH measurements/titrations. Da Rocha, Rogerio T.; Gutz, Ivano G. R.; do Lago, Claudimir L. J. Chem. Educ. 1995, 72, 1135.
Laboratory Equipment / Apparatus |
Electrochemistry |
Titration / Volumetric Analysis |
Ion Selective Electrodes |
Aqueous Solution Chemistry |
Acids / Bases |
Laboratory Management |
pH
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From Titration Data to Buffer Capacities: A Computer Experiment for the Chemistry Lab or Lecture Roy W. Clark, Gary D. White, Judith M. Bonicamp, and Exum D. Watts Provides titration curve data that students can plot and analyze using spreadsheets to develop student understanding of pH, derivatives, buffer capacity, and the behavior of dilute buffers; includes sample graphs and analysis. Clark, Roy W.; White, Gary D.; Bonicamp, Judith M.; Watts, Exum D. J. Chem. Educ. 1995, 72, 746.
Acids / Bases |
pH |
Titration / Volumetric Analysis |
Chemometrics
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Teaching the Truth about pH Hawkes, Stephen J. -log[H+] is only an approximation to pH; how to teach pH to avoid misleading students. Hawkes, Stephen J. J. Chem. Educ. 1994, 71, 747.
pH |
Acids / Bases |
Aqueous Solution Chemistry |
Equilibrium
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A recipe for the preparation of a pH 7.00 calibration buffer Jackman, Donald C. Simple recipe for preparation of a pH 7.00 calibration buffer based on the NIST standard. Jackman, Donald C. J. Chem. Educ. 1993, 70, 853.
Acids / Bases |
Laboratory Management |
pH
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The acid-base package Ramette, Richard W.; Holmes, Jon L. Software that will calculate theoretical titration curve data and the pH for any mixture of acids and/or bases. Ramette, Richard W.; Holmes, Jon L. J. Chem. Educ. 1992, 69, 1010.
Acids / Bases |
pH |
Titration / Volumetric Analysis
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A low-cost pH meter for the classroom. Harris, David L.; Harris, Daniel C. Design of an inexpensive yet precise pH meter for classroom use. Harris, David L.; Harris, Daniel C. J. Chem. Educ. 1992, 69, 563.
Laboratory Equipment / Apparatus |
pH |
Acids / Bases
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A modified graphical method for acid-base equilibria Nakagawa, Kuniaki A method based on logarithmic diagrams for finding the pH values for various systems in acid-base equilibria. Nakagawa, Kuniaki J. Chem. Educ. 1990, 67, 673.
Acids / Bases |
Equilibrium |
pH
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The pH of any mixture of monoprotic acids and bases Herman, D. P.; Booth, K. K.; Parker, O. J.; Breneman, G. L. 115. Bits and pieces, 44. The pH of any mixture of monoprotic weak and strong acids and bases can be calculated. A curve can also be plotted for the titration of the mixture by any monoportic weak or strong acid or base. Herman, D. P.; Booth, K. K.; Parker, O. J.; Breneman, G. L. J. Chem. Educ. 1990, 67, 501.
Acids / Bases |
Titration / Volumetric Analysis |
pH
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pH measurements on the overhead projector Solomon, Sally; High, Nancy Universal indicator solution and a corresponding pH indicator chart are used to make pH measurements of an overhead projector where the results are visible to all students in a large lecture hall. Solomon, Sally; High, Nancy J. Chem. Educ. 1987, 64, 964.
pH |
Acids / Bases |
Dyes / Pigments
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Buffer capacity: An undergraduate laboratory experiment Russo, Steven O.; Hanania, George I. H. A quantitative experiment that can demonstrate buffer action and the measurement of buffer capacity, for a given buffer system, over a range of pH. Russo, Steven O.; Hanania, George I. H. J. Chem. Educ. 1987, 64, 817.
Acids / Bases |
pH |
Aqueous Solution Chemistry
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Density gradient columns for chemical displays Guenther, William B. An important advantage of these demonstrations of complex chemistry is that students can observe them over a period of time as they grasp concepts of solution equilibria. Guenther, William B. J. Chem. Educ. 1986, 63, 148.
Acids / Bases |
pH |
Coordination Compounds |
Metals
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An invitation to experiment with an experiment Phanstiel, Otto Students are asked to develop an experiment in which they isolate an acid / base indicator from a flower and determine the pH at which it changes color. Phanstiel, Otto J. Chem. Educ. 1985, 62, 522.
Acids / Bases |
Dyes / Pigments |
pH
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Visualization of buffer action and the acidifying effect of CO2 Schonbeck, Niels D. Includes a discussion of the physiological buffering of CO2 in the human body. Schonbeck, Niels D. J. Chem. Educ. 1985, 62, 436.
Acids / Bases |
pH
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A simple demonstration of buffer action Duerst, Marilyn D. A simple yet impressive visual demonstration of buffer action. Duerst, Marilyn D. J. Chem. Educ. 1985, 62, 435.
Acids / Bases |
pH
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Why teach solution equilibrium? Butler, James N. What are the most important aspects of solution equilibrium to teach at the elementary level? Butler, James N. J. Chem. Educ. 1984, 61, 784.
Equilibrium |
Solutions / Solvents |
Acids / Bases |
pH
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A pocket calculator program for the solution of pH problems via the method of successive approximations Guida, Wayne C. 37. Bits and pieces, 14. A description of a pocket calculator program for the solution of pH problems via the method of successive approximations . Guida, Wayne C. J. Chem. Educ. 1983, 60, 101.
pH |
Acids / Bases |
Chemometrics
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Thermal buffers: An illustrative analogy Macomber, Roger S. An analogy between acid-base buffer behavior and the thermal behavior of a two-phase (solid and liquid) system. Macomber, Roger S. J. Chem. Educ. 1979, 56, 710.
Acids / Bases |
pH
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The standardization of pH meters: A comparison of procedures for different types of instruments Lund, Walter Discusses the various approaches to the standardization of pH meters and the limitations of the various procedures. Lund, Walter J. Chem. Educ. 1979, 56, 129.
Instrumental Methods |
pH |
Laboratory Equipment / Apparatus |
Laboratory Management |
Calibration |
Acids / Bases
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The pH concept Kolb, Doris Reviews pH, the pH scale, pH calculations, buffered solutions, and measuring pH. Kolb, Doris J. Chem. Educ. 1979, 56, 49.
pH |
Aqueous Solution Chemistry |
Acids / Bases
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Buffer effect demonstration on the overhead projector Hobe, Paul G., Jr. Illustrates that one drop of dilute acid or base will change the pH of water by a large amount while larger amounts can be added to a buffer solution before any change is noted. Hobe, Paul G., Jr. J. Chem. Educ. 1979, 56, 47.
Acids / Bases |
pH
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Conjugate acid-base mixtures in the general chemistry laboratory. A comprehensive buffer experiment Wiger, George R.; de la Camp, Ulrich A very exact and detailed procedure for a comprehensive buffer experiment is presented in this paper. Wiger, George R.; de la Camp, Ulrich J. Chem. Educ. 1978, 55, 401.
Acids / Bases |
pH
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Emphasis on acids and bases J. Chem. Educ. Staff Considers the acidity or basicity in soils and natural waters; the acid-base balance in body chemistry; acidic and basic foods; the approximate pH values of common fluids; examples of acidic, basic, and neutral drugs; and the commercial preparation of nitric acid. J. Chem. Educ. Staff J. Chem. Educ. 1977, 54, 626.
Acids / Bases |
Water / Water Chemistry |
Food Science |
Applications of Chemistry |
pH |
Drugs / Pharmaceuticals
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Effect of Ionic Strength on Equilibrium Constants Seymour, M. D.; Fernando, Quintus Involves the determination of the acid dissociation constant of bromcresol green by a spectrophotometric method; using a graphing calculator, each student can perform the laboratory work and obtain his own data set. Seymour, M. D.; Fernando, Quintus J. Chem. Educ. 1977, 54, 225.
Acids / Bases |
Aqueous Solution Chemistry |
Equilibrium |
pH
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An Effective demonstration of the behavior of indicators and biochemicals in buffers Lerman, Charles L. The author has found this demonstration of buffers useful for both freshman level courses and as a refresher in biochemistry. Lerman, Charles L. J. Chem. Educ. 1976, 53, 634.
Acids / Bases |
pH
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A new buffer demonstration Friedman, Norman An Alka-Seltzer tablet in water is used as a buffer system and its resistance to changes in pH are compared to solutions of buffered aspirin and aspirin. Friedman, Norman J. Chem. Educ. 1975, 52, 605.
Acids / Bases |
pH |
Consumer Chemistry
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A new chemistry program for nursing and allied health students Stanitski, Conrad L.; Sears, Curtis T., Jr. Outlines and discusses the topics considered in a chemistry program for nursing and allied health students. Stanitski, Conrad L.; Sears, Curtis T., Jr. J. Chem. Educ. 1975, 52, 226.
Nonmajor Courses |
Applications of Chemistry |
Medicinal Chemistry |
Oxidation / Reduction |
Catalysis |
Acids / Bases |
pH |
Metabolism |
Drugs / Pharmaceuticals
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Solubility and pH Calculations (Butler, James N.) Ramette, R. W.
Ramette, R. W. J. Chem. Educ. 1964, 41, A970.
Aqueous Solution Chemistry |
Precipitation / Solubility |
pH |
Acids / Bases |
Chemometrics |
Enrichment / Review Materials
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Overhead projection with the pH meter Hoff, Darrel B. Describes a means of projecting an image of a pH meter. Hoff, Darrel B. J. Chem. Educ. 1964, 41, 662.
pH |
Acids / Bases |
Aqueous Solution Chemistry |
Titration / Volumetric Analysis
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A versatile and inexpensive pH recording electrometer Malmstadt, H. V. Presents the design and operation of a modular pH unit with automatic temperature compensation. Malmstadt, H. V. J. Chem. Educ. 1964, 41, 148.
pH |
Acids / Bases |
Aqueous Solution Chemistry
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Easily prepared wide range buffer series Carmody, Walter R. A series of buffers with pH values ranging from 2.0 to 12.0 that requires the preparation of only two stock solutions and requires only three common chemicals. Carmody, Walter R. J. Chem. Educ. 1961, 38, 559.
Aqueous Solution Chemistry |
Acids / Bases |
pH |
Laboratory Management
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pH meters (continued) Lewin, S. Z. Considers the standardization, calibration, and testing of pH meters, as well as Beckman pH meters. Lewin, S. Z. J. Chem. Educ. 1959, 36, A595.
Instrumental Methods |
pH |
Acids / Bases |
Aqueous Solution Chemistry |
Calibration
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Research project for general chemistry laboratory Schwolow, Jean In order to modify the routine experiment in which students know the answers before ever entering the laboratory, freshmen were presented with a simulated research project connected with acids, bases, and pH measurements. Schwolow, Jean J. Chem. Educ. 1958, 35, 416.
Undergraduate Research |
Acids / Bases |
pH |
Aqueous Solution Chemistry
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Amphoteric molecules, ions and salts Davidson, David It is the aim of this paper to call attention to the splendid opportunity amphoteric substances afford for the teaching of acid-base principles. Davidson, David J. Chem. Educ. 1955, 32, 550.
Molecular Properties / Structure |
Acids / Bases |
pH |
Aqueous Solution Chemistry
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pH approximations McBay, Arthur J. Describes the use of data from tables to approximate pH values. McBay, Arthur J. J. Chem. Educ. 1952, 29, 526.
pH |
Acids / Bases |
Aqueous Solution Chemistry
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