| Journal Articles: 28 results |
|
|
An Updated Equilibrium Machine Emeric Schultz
Describes a device that can demonstrate equilibrium and the Le Châtelier principle, as well as kinetic and thermodynamic concepts. The device consists of a leaf blower attached to a plastic container divided into two chambers by a barrier of variable size and form. Styrofoam balls can be exchanged across the barrier when various air pressures are applied by the blower.
Schultz, Emeric. J. Chem. Educ. 2008, 85, 1131.
Equilibrium |
Kinetics |
Thermodynamics
|
An Experimental Approach to Teaching and Learning Elementary Statistical Mechanics Frank B. Ellis and David C. Ellis
This article details demonstrations that show how equilibrium changes with temperature, energy, and entropy and involve exothermic and endothermic reactions, the dynamic nature of equilibrium, and Le Châtelier's principle.
Ellis, Frank B.; Ellis, David C. J. Chem. Educ. 2008, 85, 78.
Equilibrium |
Kinetics |
Statistical Mechanics |
Thermodynamics
|
Flame Emission Spectrometry in General Chemistry Labs: Solubility Product (Ksp) of Potassium Hydrogen Phthalate Frazier W. Nyasulu, William Cusworth III, David Lindquist, and John Mackin
In this general chemistry laboratory, flame emission spectrometry is used to determine the potassium ion concentration in saturated solutions of potassium hydrogen phthalate. From these data the solubility products, the Gibbs free energies of solution, the standard enthalpy of solution, and the standard entropy of solution are calculated.
Nyasulu, Frazier W.; Cusworth, William, III; Lindquist, David; Mackin, John. J. Chem. Educ. 2007, 84, 456.
Acids / Bases |
Atomic Properties / Structure |
Spectroscopy |
Equilibrium |
Quantitative Analysis |
Thermodynamics |
Titration / Volumetric Analysis |
Solutions / Solvents |
Aqueous Solution Chemistry |
Atomic Spectroscopy
|
Discovering the Thermodynamics of Simultaneous Equilibria. An Entropy Analysis Activity Involving Consecutive Equilibria Thomas H. Bindel
This activity explores the thermodynamics of simultaneous, consecutive equilibria and is appropriate for second-year high school or AP chemistry. Students discover that a reactant-favored (entropy-diminishing) reaction can be caused to happen if it is coupled with a product-favored reaction of sufficient entropy production.
Bindel, Thomas H. J. Chem. Educ. 2007, 84, 449.
Acids / Bases |
Equilibrium |
Thermodynamics
|
Give Them Money: The Boltzmann Game, a Classroom or Laboratory Activity Modeling Entropy Changes and the Distribution of Energy in Chemical Systems Robert M. Hanson and Bridget Michalek
Described here is a short, simple activity that can be used in any high school or college chemistry classroom or lab to explore the way energy is distributed in real chemical systems and as an entry into discussions of the probabilistic nature of entropy.
Hanson, Robert M.; Michalek, Bridget. J. Chem. Educ. 2006, 83, 581.
Equilibrium |
Statistical Mechanics |
Thermodynamics
|
Computer Simulations of Salt Solubility Victor M. S. Gil and João C. M. Paiva
Computer Simulations of Salt Solubility provides an animated, visual interpretation of the different solubilities of related salts based on simple entropy changes associated with dissolution: configurational disorder and thermal disorder.
Gil, Victor M. S.; Paiva, João C. M. J. Chem. Educ. 2006, 83, 173.
Thermodynamics |
Equilibrium |
Solutions / Solvents |
Precipitation / Solubility |
Computational Chemistry
|
A New Java Animation in Peer-Reviewed JCE WebWare William F. Coleman and Edward W. Fedosky
Just added to JCE WebWare, Computer Simulations of Salt Solubility uses a Java applet and Web browser to present an animated illustration of differences in the solubility of salts due to differences in the entropy of solvation.
Coleman, William F.; Fedosky, Edward W. J. Chem. Educ. 2006, 83, 173.
Computational Chemistry |
Equilibrium |
Thermodynamics |
Solutions / Solvents |
Precipitation / Solubility
|
Using Computer Simulations To Teach Salt Solubility. The Role of Entropy in Solubility Equilibrium Victor M. S. Gil and João C. M. Paiva
Pairs of salts are discussed to illustrate the interpretation of their different behavior in water in terms of the fundamental concept of entropy. The ability of computer simulations to help improve students' understanding of these chemistry concepts is also examined.
Gil, Victor M. S.; Paiva, João C. M. J. Chem. Educ. 2006, 83, 170.
Computational Chemistry |
Equilibrium |
Thermodynamics |
Solutions / Solvents |
Precipitation / Solubility
|
Microscopic Description of Le Châtelier's Principle Igor Novak
The analysis based on microscopic descriptors (energy levels and their populations) is given that provides visualization of free energies and conceptual rationalization of Le Châtelier's principle. The misconception "nature favors equilibrium" is highlighted.
Novak, Igor. J. Chem. Educ. 2005, 82, 1190.
Equilibrium |
Thermodynamics
|
JavaScript Programs To Calculate Thermodynamic Properties Using Cubic Equations of State
Cubic equations of state are widely used by chemists and chemical engineers to predict the thermodynamic properties of both pure substances and mixtures. In particular, these equations enable predictions concerning the temperature and pressure at which vaporliquid equilibrium occurs. These two educational JavaScript programs perform calculations using cubic equations of state and, equally importantly, explain how the calculations are performed.
J. Chem. Educ. 2005, 82, 960.
Enrichment / Review Materials |
Equilibrium |
Thermodynamics
|
JavaScript Programs To Calculate Thermodynamic Properties Using Cubic Equations of State Patrick J. Barrie
In this article, two JavaScript programs are described. The first program gives students the choice of five different cubic equations of state and performs calculations for pure substances. The second program predicts vaporliquid equilibrium for binary mixtures using a choice of three modern equations of state and the van der Waals mixing rules.
Barrie, Patrick J. J. Chem. Educ. 2005, 82, 958.
Enrichment / Review Materials |
Thermodynamics |
Equilibrium
|
Playing-Card Equilibrium Robert M. Hanson
A simple hands-on simulation suitable for either classroom use or laboratory investigation involves using a standard deck of playing cards to explore the statistical aspects of equilibrium. Concepts that can be easily demonstrated include fluctuation around a most probable distribution, Le Chtelier's principle, the equilibrium constant, prediction of the equilibrium constant based on probability, and the effect of sample size on equilibrium fluctuations.
Hanson, Robert M. J. Chem. Educ. 2003, 80, 1271.
Equilibrium |
Statistical Mechanics |
Thermodynamics
|
Rubber Bands, Free Energy, and Le Châtelier's Principle Warren Hirsch
Using a rubber band to illustrate Gibbs free energy, entropy, and enthalpy.
Hirsch, Warren. J. Chem. Educ. 2002, 79, 200A.
Noncovalent Interactions |
Thermodynamics |
Equilibrium
|
Determination of Ksp, ΔG0, ΔH0, and ΔS0 for the Dissolution of Calcium Hydroxide in Water: A General Chemistry Experiment William B. Euler, Louis J. Kirschenbaum, and Ben Ruekberg
This exercise utilizes low-cost, relatively nonhazardous materials presenting few disposal problems. It reinforces the students' understanding of the interrelationship of solubility, Ksp, ΔG0, ΔH0, and ΔS0.
Euler, William B.; Kirschenbaum, Louis J.; Ruekberg, Ben. J. Chem. Educ. 2000, 77, 1039.
Equilibrium |
Thermodynamics |
Titration / Volumetric Analysis
|
Chemical Equilibrium (the author replies) Banerjee, Anil
Item 7 deserves a fuller answer than was provided.
Banerjee, Anil J. Chem. Educ. 1996, 73, A262.
Equilibrium |
Thermodynamics
|
Chemical Equilibrium Logan, S. R.
Item 7 deserves a fuller answer than was provided.
Logan, S. R. J. Chem. Educ. 1996, 73, A261.
Equilibrium |
Thermodynamics
|
Thermodynamics and Spontaneity Raymond S. Ochs
Despite the importance of thermodynamics as the foundation of chemistry, most students emerge from introductory courses with only a dim understanding of this subject.
Ochs, Raymond S. J. Chem. Educ. 1996, 73, 952.
Thermodynamics |
Learning Theories |
Equilibrium
|
Teaching Chemical Equilibrium and Thermodynamics in Undergraduate General Chemistry Classes Anil C. Banerjee
Discussion of the conceptual difficulties experienced by undergraduates when dealing with equilibrium and thermodynamics, along with teaching strategies for dealing with these difficulties.
Banerjee, Anil C. J. Chem. Educ. 1995, 72, 879.
Equilibrium |
Thermodynamics
|
REACT: Exploring Practical Thermodynamic and Equilibrium Calculations Ramette, Richard W.
Description of REACT software to balance complicated equations; determine thermodynamic data for all reactants and products; calculate changes in free energy, enthalpy, and entropy for a reaction; and find equilibrium conditions for the a reaction.
Ramette, Richard W. J. Chem. Educ. 1995, 72, 240.
Stoichiometry |
Equilibrium |
Thermodynamics |
Chemometrics
|
Thermodynamics of the rhodamine B lactone zwitterion equilibrium: An undergraduate laboratory experiment Hinckley, Daniel A.; Seybold, Paul G.
An experiment to derive thermodynamic values from a thermochromic equilibrium that uses a commercially available dye, attains equilibrium rapidly, and employs a simple, single-beam spectrophotometer.
Hinckley, Daniel A.; Seybold, Paul G. J. Chem. Educ. 1987, 64, 362.
Thermodynamics |
Dyes / Pigments |
Spectroscopy |
Equilibrium
|
Le Châtelier's principle, temperature effects, and entropy Campbell, J. Arthur
A useful extension of Le Chatelier's Principle to predict concentration, pressure, and temperature effects solely from the equation for the net reaction.
Campbell, J. Arthur J. Chem. Educ. 1985, 62, 231.
Equilibrium |
Thermodynamics
|
Thermodynamic changes, kinetics, equilibrium, and LeChatelier's principle Hansen, Robert C.
A series of demonstrations in which water in beakers and the flow of water between beakers is used to represent the components of an exothermic chemical reaction and the flow and quantity of thermal energy involved in chemical changes.
Hansen, Robert C. J. Chem. Educ. 1984, 61, 804.
Equilibrium |
Kinetics |
Thermodynamics
|
Le Châtelier's principle: the effect of temperature on the solubility of solids in liquids Brice, L. K.
The purpose of this article is to provide a rigorous but straightforward thermodynamic treatment of the temperature dependence of solubility of solids in liquids that is suitable for presentation at the undergraduate level. The present discussion may suggest how to approach the qualitative aspects of the subject for freshman.
Brice, L. K. J. Chem. Educ. 1983, 60, 387.
Thermodynamics |
Liquids |
Solids |
Chemometrics |
Equilibrium
|
An apparent contradiction in the application of the principle of Le Chtelier Mellon, E. K.
Unless some care is exercised, the application of free energy concepts in situations where marked temperature changes occur can lead to apparent contradictions like the one described in this paper.
Mellon, E. K. J. Chem. Educ. 1979, 56, 380.
Equilibrium |
Thermodynamics
|
Physical chemistry of the drinking duck Plumb, Robert C.; Wagner, Robert E.
The operation of the drinking bird is easily understood in terms of a few elementary physical chemistry principles.
Plumb, Robert C.; Wagner, Robert E. J. Chem. Educ. 1973, 50, 213.
Thermodynamics |
Phases / Phase Transitions / Diagrams |
Equilibrium
|
Sealed tube experiments Campbell, J. A.
Lists and briefly describes a large set of "sealed tube experiments," each of which requires less than five minutes to set-up and clean-up, requires less than five minutes to run, provides dramatic results observable by a large class, and illustrates important chemical concepts.
Campbell, J. A. J. Chem. Educ. 1970, 47, 273.
Thermodynamics |
Crystals / Crystallography |
Solids |
Liquids |
Gases |
Rate Law |
Equilibrium
|
Temperature dependence of equilibrium: A first experiment in general chemistry Mahan, Bruce H.
This experiment uses cooling curves to derive the expression for the temperature dependence of the equilibrium constant.
Mahan, Bruce H. J. Chem. Educ. 1963, 40, 293.
Equilibrium |
Thermodynamics
|
Praseodymium tetrafluoride Perros, Theodore P.; Munson, Thomas R.; Naeser, Charles R.
In spite of the experimental failures to prepare praseodymium tetrafluoride, there is strong evidence for its possible formation to be found by calculating the equilibrium constants for some of the reactions by which this compound might be prepared.
Perros, Theodore P.; Munson, Thomas R.; Naeser, Charles R. J. Chem. Educ. 1953, 30, 402.
Oxidation State |
Equilibrium |
Thermodynamics
|
|
