71 Results
A Pedagogical Simulation of Maxwell's Demon Paradox   
(Software, Instructional Material (1))
Maxwell's demon was conceived by James Clerk Maxwell in 1871 to illustrate the statistical basis of thermodynamics (1), and the concept has since formed an arena for investigation and clarification of many concepts in thermodynamics (2). Chemistry students often have difficulty developing an intuitive knowledge of some concepts in thermodynamics. A Pedagogical Simulation of Maxwell's Demon aims to help make these concepts more understandable for students. Teaching thermodynamics from the microscopic point of view can help students develop an intuitive understanding of its concepts. This program simulates, at the microscopic level, two gas chambers with an opening between them. The program allows students or their instructors to set up simulations that illustrate the thermodynamics and statistical behavior of the system. The user determines the basis for whether the demon permits or denies passage of particles through the opening using information from the microscopic level, such as specific particle velocity. Students can track and analyze how this affects particle distribution, thermal equilibrium, relaxation time, diffusion, and distribution of particle velocities.
A Lattice Energy Spreadsheet   
(Software, Instructional Material (1))
A Lattice Energy Spreadsheet is a tool that easily calculates lattice energies. It also illustrates the relation between crystal structure, coordination number, and ionic radii. A Lattice Energy Spreadsheet contains five related worksheets: Lattice Energy, MX Structure Map, Kapustinsky Lattice Energy, Directions, and Discussion, each described below. In the Lattice Energy worksheet, the lattice energy of many binary compounds can be calculated in about a dozen mouse clicks. An element is selected, and the radius corresponding to the desired charge and coordination number is selected. The same is done for the counter ion, and the anticipated crystal structure of the compound is chosen (rock salt, wurtzite, etc.). The lattice energy is then calculated. This sheet uses enthalpies of formation of monatomic gaseous atoms from the elements, ΔH°form, to calculate lattice energies. The results are more accurate than the values obtained by simply summing enthalpies of fusion and vaporization. The results of the corresponding Born-Haber cycle are also graphed on this sheet.
Enthalpy of Fusion and Enthalpy of Vaporization   
(Other (1))
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Entropy, Randomness, and Disorder   
(Other (1))
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Thermodynamic Probability W and Entropy   
(Other (1))
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Thermodynamic Terms and Conventions   
(Other (1))
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Internal Energy   
(Other (1))
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Predicting the Direction of a Reaction   
(Other (1))
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Energy and the Formation of Ions   
(Other (1))
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
The Effect of a Change in Temperature   
(Other (1))
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Hess' Law   
(Other (1))
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Energy   
(Other (1))
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Maximum Useful Work   
(Other (1))
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
The Free Energy   
(Other (1))
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Including the Surroundings   
(Other (1))
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Measuring the Entropy   
(Other (1))
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Standard Molar Entropies   
(Other (1))
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Getting Acquainted with Entropy   
(Other (1))
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Fossil Fuels and the Energy Crisis   
(Other (1))
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
State Functions   
(Other (1))
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Enthalpy   
(Other (1))
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Standard Enthalpies of Formation   
(Other (1))
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
TNT Detonation   
(Movie/Animation, Audio/Visual (7))
TNT is stable in the presence of shock, but can be detonated by adding a chemical priming agent.
Entropy   
(Movie/Animation, Audio/Visual (4))
These processes are shown in reverse. The situations shown are so highly improbable that we would not expect to observe them in nature.
Endothermic Reaction   
(Movie/Animation, Audio/Visual (3))
Solid barium hydroxide octahydrate (Ba(OH)2*8H2O) and ammonium thiocyanate (NH4SCN) are mixed in a beaker, which is then placed on a few drops of water on a small board. The reaction that occurs is highly endothermic.
Chemiluminescence   
(Movie/Animation, Audio/Visual (2))
Luminol and light sticks are demonstrated.
Enthlapy-Thermodynamics   
(Movie/Animation, Audio/Visual (10))
Reactions and demonstrations the explore thermodynamic concepts.
Two Solids (GCMP)   
(Interactive Simulation, Software (1))
Two Solids: this is a resource in the collection "General Chemistry Multimedia Problems". When two solids barium hydroxide octahydrate, Ba(OH)2. 8H2O and ammonium thiocyanate, NH4SCN are mixed, they react. We will explore the thermodynamics of the reaction. General Chemistry Multimedia Problems ask students questions about experiments they see presented using videos and images. The questions asked apply concepts from different parts of an introductory course, encouraging students to decompartmentalize the material.
Disorder (GCMP)   
(Interactive Simulation, Software (1))
Disorder: this is a resource in the collection "General Chemistry Multimedia Problems". A spontaneous change is one that has a natural tendency to occur without needing to be driven by an external influence. This problem will explore the influence of entropy, a measure of disorder, on the spontaneity of a few processes. General Chemistry Multimedia Problems ask students questions about experiments they see presented using videos and images. The questions asked apply concepts from different parts of an introductory course, encouraging students to decompartmentalize the material.
Thermodynamics : EntropyPhaseChange (13 Variations)   
(Assessment Material (1))
Aluminum can be evaporated in a vacuum to form highly reflective coatings. Aluminum boils at 2792K and has a heat of vaporization of 70.0 kcal/mol. Calculate the entropy change for the vaporization of one mole of aluminum.
Thermodynamics : ATPFromGlucose (8 Variations)   
(Assessment Material (1))
When glucose is oxidized in the human body it releases a lot of Gibbs free energy. Rather than waste this free energy, the body stores much of it in the form of ATP. The following reaction shows this process of storing some of the energy from glucose in ATP. This is an example of coupled reactions in a biological system.

The label on a can of Coke says that it contains 39 g of sugar. Assume that all of the sugar is glucose (even though it isn't), and calculate how many moles of ATP can be produced theoretically by the oxidation of 39.0 g of glucose.
Thermodynamics : GibbsFromHSandT (5 Variations)   
(Assessment Material (1))
On the space shuttle, the carbon dioxide produced by the astronauts is handled by an environmental control system that utilizes the following reaction.

H° = -138.4 kJ and S° = -139 J/K Calculate G° at 25°C for this reaction.
Thermodynamics : DetermineRxnFavored (8 Variations)   
(Assessment Material (1))
When industrial plants burn coal, sulfur dioxide is produced. Sulfur dioxide is a primary pollutant that contributes to both industrial smog and acid rain. Is this process of producing sulfur dioxide product-favored?

Using

Thermodynamics : CalcMinSpontTemp (9 Variations)   
(Assessment Material (1))
Calculate the minimum temperature above which the following reaction will be product-favored (spontaneous).


Thermodynamics : CalcDeltaS (9 Variations)   
(Assessment Material (1))
Using , calculate the entropy change for the reaction.
Thermodynamics : CalcDeltaG (14 Variations)   
(Assessment Material (1))
Using , calculate the Gibbs free energy change for the following reaction which produces the metal zinc from its ore zinc(II) oxide.
2 ZnO(s) 2 Zn(s) + O2(g)

Thermodynamics : ThermoKinStability (4 Variations)   
(Assessment Material (1))
Compare white and grey tin, both of which exist as solid phases of tin near room temperature.

Phase Hof (kJ/mol) So (J/(K*mol))
white tin 0 51.5
grey tin -2.1 44.8

Which type of stability does each exhibit at 40 oC?

white tin {1:MULTICHOICE:kinetically stable#No, that's incorrect.~=thermodynamically stable#Correct!}

grey tin {1:MULTICHOICE:=kinetically stable#Correct!~thermodynamically stable#No, that's incorrect.}

Thermodynamics : InterpretKandDeltaG (16 Variations)   
(Assessment Material (1))
The thermodynamic equilibrium constant for the following reaction is 0.15 at 1227°C.
2 SO2(g) + O2(g) 2 SO3(g)
Check the box for each true statement.
Thermodynamics : ProbabilityEnergyDist (23 Variations)   
(Assessment Material (1))
Consider a system that has two indistinguishable molecules that can occupy three different energy levels (having energies of 1kJ, 2kJ and 3kJ, respectively). What is the probability that the molecules will have a total energy of 2 kJ?
Thermodynamics : GeneralThermo (6 Variations)   
(Assessment Material (1))
Which of the following statements is an inaccurate statement about thermodynamics?
Thermodynamics : ConservGibbsEnergy (6 Variations)   
(Assessment Material (1))
Which of the following best illustrates conservation of Gibbs free energy?
Thermodynamics : PredictEntropyChange (10 Variations)   
(Assessment Material (1))
For each of the following processes, indicate whether you expect the entropy change of the system to be positive or negative.
Thermodynamics : CompareEntropyQual (16 Variations)   
(Assessment Material (1))
Indicate which substance in each of the following pairs of substances you expect to have higher entropy. Assume that you have a mole of each substance and all substances are at the same temperature.
Protecting Citrus Trees from Freezing with Freezing Water   
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A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Energy from Aerobic vs. Anaerobic Fermentation   
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A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Gibbs Free Energy in Biology   
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A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Measuring the Enthalpy Change Lecture Demonstrations   
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A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Cooking Efficiencies of Pots and Pans   
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A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Enthalpy of Fusion and Enthalpy of Vaporization Lecture Demonstrations   
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A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Domestic Energy Storage in Phase Change Materials (PCMs)   
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A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Original Writings of Joseph Black on the Melting of Ice (ca. 1760)   
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A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Ice Houses   
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A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Why are Air Conditioners Rated in Tons of Cooling Capacity   
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A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Water on Mars   
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A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
The Higher Heating Value and Lower Heating Value of Various Fuels   
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A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Heat Capacities of Minerals   
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A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Cooling of Plutons and Young Earth Creationism   
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A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Muscle Energy from ATP   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
The Food Energy in a Marshmallow   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Standard Enthalpies of Formation in Geology-Calculating the Heat Released by Serpentinization in the Lost City   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
ChemPaths 104 F Apr 1   
()
Today in Chem 104: * Lecture: Review Session * Homework #8 due by 11:55 PM F Apr 1
ChemPaths 104 W Mar 30   
()
Today in Chem 104: * Lecture: Gibbs Free Energy * Reading: Kotz: Ch. 19, Sec. 5-7 Moore: Ch. 18, Sec. 5-8 * Homework #8 due by 11:55 PM F Apr 1 * Quiz in second discussion section this week. * Lab this week is #11, Electrochemical Cells
ChemPaths 104 M Mar 28   
()
Today in Chem 104: * Lecture: Entropy * Reading: Kotz: Ch. 19, Sec. 1-4 Moore: Ch. 18, Sec. 1-4 * Homework #8 due by 11:55 PM F Apr 1 * Quiz in second discussion section this week
Heat Capacities Lecture Demonstrations   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Thermal Mass for Heat Storage   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
The Thermodynamics of Pizza   
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A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
The Amazing Water Diet   
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A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Heat Transfer in Nuclear Power Plants   
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A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Thermoregulation and Hydration   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
The Amazing Ice Diet   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Carbide Cannon   
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A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.