Chemistry 30 Thermodynamics Lab Resources

General Comments

Lab activities and demonstrations should reinforce the difference between endothermic and exothermic reactions and give students the opportunity to measure energy changes during physical and chemical reactions (calorimetry) and calculate heats of reaction. Hess's Law may also be reinforced by lab studies. Temperature changes during change of phase is a useful lab that may be used to help students understand the conversion between kinetic and potential energy as it relates to chemical bonding.

Most chemistry texts are associated with a student lab manual. These lab manuals provide complete descriptions of materials and equipment needed, safety precautions to follow, and procedures to follow. Most of the lab activities suggested below may be found in these manuals and will not be reproduced here; only a general overview is provided.

Which lab activities are carried out will depend on the degree of of teacher supervision and what lab materials and facilities are available. Many of the labs provided in this resource will include a set of data that the students may use to perform calculations, construct graphs, and answer questions in case they are not able to actually perform the experiment.

Some labs have a link to a video that demonstrate the lab.

Links to web sites with appropriate labs are also provided.

Organized by Topic

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Topic	Type
Energy - Molecular motion	Simulation	Molecular motion at different temperatures
Heat transfer	Simulation	Heat transfer between two metals
Energy Conversion	Lab	Heating and Cooling Curves - sample data is provided
Exothermic Reactions	Movie	An exothermic reaction. This movie demonstrates the thermite reaction, a highly exothermic reaction. This site contains many other excellent videos.
Exothermic Reactions	Movie	An exothermic reaction. This movie shows the exothermic reaction between aluminum and bromine for form aluminum bromide.
Exothermic Reactions	Movie	The formation of water, a spontaneous exothermic reaction.
Endothermic Reactions	Demonstration and Movie	A spontaneous endothermic reaction. This demonstration (a movie is also available) has become one of my favorites! The highly endothermic reaction between Ba(OH)₂·8H₂O and NH₄Cl causes a thin film of water to freeze. There is a rapid and dramatic decrease in temperature. Excellent as well as a demonstration of the importance of entropy on reaction spontaneity.
Exothermic/ Endothermic Reactions	Lab	Endothermic & Exothermic Reactions - This quick lab requires minimal equipment and materials. A variety of salts are dissolved in water in test tubes; students are able to feel the test tube to determine if the dissolving process was endothermic or exothermic.
Calorimetry	Demonstration Lab	An Introduction to Calorimetry - a short and simple introduction to calorimetry. Heat of Solution - Calorimetry. A simple lab to perform that introduces students to the procedure and calculations required for basic calorimetry. Sample data is provided.
Hess's Law	Lab	Heats of Reaction - Hess's Law. Using calorimetry, students investigate an example of Hess's Law. Involves strong acids and bases - supervision required. Sample data is provided.
Stability of Compounds	Movie	The stability of NI₃. The compound is so unstable it explosively decomposes when touched with a feature.
Entropy	Demonstration	A spontaneous endothermic reaction. Excellent and very simple demonstration of the role of entropy in reaction spontaneity.

Labs

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Link to Lab	Student Version
Heating and Cooling Curves (Teaching Notes)	Word	RTF	PDF
Endothermic & Exothermic Reactions	HTML format only
Heat of Solution - Calorimetry	Word	RTF	PDF
Heats of Reaction - Hess's Law	Word	RTF	PDF

Demonstrations & Quick Labs

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Print demonstration ideas: Word | RTF | PDF
Want more ideas? Use keywords: "chemistry demonstrations" to find additional ideas.

An Introduction to Calorimetry - Lesson 1.6

Add a measured mass of water (about 150 g) to a styrofoam cup (a simple calorimeter). Measure the starting water temperature. Measure the mass of about 2.0 g of coarse NaCl. Add the salt to the water and stir, being sure to note the maximum temperature change. The heat of solution may be calculated (see the Heat of Solution Lab for calculations).

A Spontaneous Endothermic Reaction - Lesson 1.5 and Lesson 3.1

Place a few drops of water on an inverted petri dish. In a 50 mL beaker combine approximately 20g Ba(OH)₂·8H₂O with 10g NH₄Cl (NH₄SCN could be used instead) . Stir to mix. The endothermic reaction will freeze the water, allowing you to lift the beaker and attached petri dish.

This demonstration is useful in that it also demonstrates an endothermic reaction that is spontaneous and would be useful to do during the discussion of entropy and Gibbs Free Energy (Lesson 3). Randomness is increased greatly during this reaction, as two solids react to form a solution and a gas. The reaction:

2 NH₄Cl_(s) + Ba(OH)₂·8H₂O_(s) → 2 NH_{3 (g)} + Ba²⁺_(aq) + 2 Cl^-_(aq) + 10 H₂O_(l)

(http://chemmovies.unl.edu/chemistry/dochem/DoChem096.html )

Endothermic and Exothermic Reactions - Lesson 1.5

A quick lab or demonstration to illustrate endothermic and exothermic reactions. Small amounts of various salts are dissolved in water in a test tube. Students can feel the temperature change by touch. Salts that could be used: CaCl₂, NH₄Cl, LiCl, KNO₃ . Follow the link for details.

Simulations & Movies

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Particulate nature of matter view of a metal at different temperatures

A nice simulation of how temperature and molecular motion are related. Very simple to run.

Source: Chemical Education Resource Group, Iowa State University

Heat transfer

Illustrates how heat transfers from a hotter metal sample to a cooler sample until thermal equilibrium is reached.

Source: Chemical Education Resource Group, Iowa State University

Changes of Phase and Temperature Change

An excellent short movie with audio illustrating and explaining how temperature remains constant during change of phase.

Source: Prentice Hall General Chemistry: Principals and Modern Applications

An Exothermic Reaction

The thermite reaction. An excellent video. Many other useful videos at this site

Source: Prentice Hall: General Chemistry: Principals and Common Applications

An Endothermic Reaction

A nice quicktime movie of an endothermic reaction. This could easily be done as a lab demonstration.

Source: University of Nebraska - Lincoln. ChemMovies Server collection.

Heat of Solution of Ammonium Nitrate

A very good, simple simulation allowing students to record data and calculate the heat of solution of ammonium nitrate. An alternative to the Heat of Solution Lab. Students may change the mass of the water and the ammonium nitrate used.

Source: Blauch, David N. Chemistry @ Davidson, Virtual Chemistry Experiments. http://www.chm.davidson.edu/ChemistryApplets/index.html

Decomposition of NI₃

This compound is so unstable it explosively decomposes when touched by a feature.

Source: Prentice Hall General Chemistry: Principals and Modern Applications

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Chemistry 30

Thermodynamics Teaching Resources

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General Comments

Activities organized by topic

Suggested lab activities

Demonstration ideas

External links to simulations & movie clips

General Comments

Organized by Topic

Labs

Demonstrations & Quick Labs

Simulations & Movies