First year

27 Jun 2016
Evaluation Methods: 

The practical exam (uploaded) is used as a metric to determine how well students are capable of answering a science question they haven't seen before on their own.  In other words, the practical exam tests them on their understanding of the material, and the scientific method itself.  If you'd like to measure this against students who have performed the experiment, but did not participate in a discussion session following the experiment, the practical exam scores should give you a measure for how students compare.  The questions asked on the practical exam are designed to be as objective as possible to eliminate variation in grading between sections.

Evaluation Results: 

TBA.

Description: 

This learning object is aimed at getting students to think critically about the data they collect in lab as they collect the data similar to how chemists typically conduct research.  They will be given a pre-lab video and a procedure prior to lab, conduct the experiment, and then upload their data to an Excel spreadsheet.  Students will then stay in their group to discuss the questions given to them on the worksheet in class with the instructor, and are allowed to continue working on them as a group up until the due date.

Class data from the original experiment will be uploaded to a public Excel spreadsheet that students will have access to in lab and at home, where the averages and standard deviation will be automatically calculated for them.  Students will be responsible for all other statistical analysis.  TVs, computers, or projectors are required in the lab in order to project data to the students.  Directly after the experiment, students will enter a discussion section with a worksheet to work on as a group that relates the collected data back to the original lecture on the topic covered in the experiment.

Course Level: 
Prerequisites: 
Learning Goals: 

The purpose of this Learning Object is to teach students not only a difficult concept such as "what is electrochemical potential", but also to teach students how to think about a science question, write a hypothesis, write a procedure to answer said hypothesis, analyze the data, discuss the results as a group, and make a conclusion about their original hypothesis.  Although this learning object is written for a general chemistry electrochemistry experiment, it can be easily modified to fit any laboratory experiment in any level of college chemistry (including organic chemistry, biochemistry, etc.  The end of the semester for a course that incorporates this template involves a practical exam.  In this exam, students are given a science question related to one of the experiments they conducted during the semester such that they use the same techniques used in the original experiment, but answers a far different question.  With their laboratory notebooks and previous procedure available to them during the exam, the instructor will be required to not assist the students (outside of safety and waste disposal concerns) in any way regarding the exam.

Corequisites: 
Equipment needs: 
  • TV, computer or projector to project data for students to look at class data.
  • Proper aqueous solutions and electrodes needed for the experiment outlined in the experimental procedure.
  • If desired, a potentiostat.  However, students should be able to design simple galvanic cells to answer the questions.
  • Solutions should be prepared before the laboratory experiment and practical exams are administered.  However, it is up to your discretion whether you want your students to also make the solutions themselves.
Implementation Notes: 
  • Lab should take ~2-2.5 hours
  • Discussion should be ~1 hr
  • DIfferent practical exams for different days in which the lab is being taught, in order to prevent students from sharing what the lab is about
  • Students should know what experiment the practical exam will be based on, but should not know the exact question being asked until the day of the exam.
  • Worksheets should be due 1 week after the lab, even though students discuss the questions that day.  This gives them time to complete the assignment.
  • Questions on discussion worksheet should be difficult, given that they have the instructor and students within their group to talk to for help.
  • For the practical exam, the solutions should be prepared beforehand to focus their efforts on answering the questions rather than making solutions and preparing to answer the questions. However, it is up your discretion.
Time Required: 
~3-4 hrs
27 Jun 2016

Will it Float? Density of a Bowling Ball Activity

Submitted by Terrie Salupo-Bryant, Manchester University
Evaluation Methods: 

I collect the group activity sheets at the end of class and check if their procedure, calculations and conclusions are correct.

They have at least one or two exam questions on the chapter test that require them to apply density concepts and calculations. I haven't saved their responses in the past, but will do so when I use this activity in the future.

On the ACS General portion of the GOB standardized exam, they are required to calculate volume given the mass and density of a substance.

Evaluation Results: 

Usually when I check each group's original calculations during class, 3 to 4 groups out of nine will have made at least one calculation error (e.g. failure to convert from U.S. to metric units, incorrect calculation of radius). At the end of class usually 1 or 2 groups still have an error somewhere in their calculation. On occasion, one group may not make the correct relationship between their calculated density of the ball, the reported density of water, and whether the ball sinks or floats.

On the ACS standardized GOB exam, the number of students who were able to calculate volume given density and mass ranged from 67% to 75% over the past four years of teaching this introductory chemistry course.

Description: 

This activity was adapted from the J. Chem. Ed. article, “Discrepant Event: The Great Bowling Ball Float-Off.” In this activity students use a bowling ball and some basic materials to predict whether the ball will sink or float in a tub of liquid. 

Students in groups of 3 or 4 are assigned a bowling ball. For conventional bowling balls (circumference ranging from 26.704 inches to 27.002 inches[1]) those weighing less than 12 pounds will float and those weighing more than 12 pounds will sink. I have a variety of bowling balls (the bowling alleys I visited were more than happy to donate a ball to science), so the answer to the question, “Will it float?” depends on which ball they were assigned. They may only answer the question using available materials: bowling ball, string, ruler, graduated cylinder, calculator, textbook, balance, and a handout of geometric equations. They are also asked further questions that probe their understanding of density.                                                                                                       

[1] “USBC Equipment Specifications and Certifications Manual” updated April 2016, www.Bowl.com <accessed June 25, 2016>, p. 6.

Learning Goals: 

Students will be able to:

1.      Calculate density from mass and volume.

2.      Convert from standard U.S. units to metric units.

3.      Use density to predict whether an object will sink or float in water. 

Prerequisites: 
Course Level: 
Topics Covered: 
Corequisites: 
Equipment needs: 

One bowling ball for each group of 3-4 students, a balance that can measure in pounds, string, rulers, graduated cylinders, cork rings to hold bowling balls, large tub of water.

Subdiscipline: 
Implementation Notes: 

I don’t mention the word “density” in my introduction of the activity though they should have done the textbook reading on density prior to coming to class.  I offer a graduated cylinder to account for the holes, but in four years of doing this activity only one student has inquired about using one to make the volume correction. The results still come out fine if the volume correction is ignored. My 12 pound bowling ball eventually sinks though the average density that students calculate for this ball is slightly less than the density of the water.

You may want to pose the following questions to students:

Do the holes make a difference in your calculations?

Can you assume that the liquid in the tub is water?  Does it make a difference what the liquid is?

Will the density of the bowling ball change if you cut it in half?  Will it still float/sink?

 A common misconception is that whether it floats depends on mass alone. I demonstrate this is not the case by putting a marble in the tub with a bowling ball that floats. Considering mass alone does not account for the fact that the marble sinks and the ball floats.

 

Time Required: 
One 50 minute class period
27 Jun 2016

Solid State Stoichiometry Online

Submitted by George Lisensky, Beloit College
Evaluation Methods: 

We provide a built solid state 3D physical model that the students had not previously seen as a quiz question where students are asked to show their work in calculating the stoichiometry

See the evaluation questions file and activity answer key in the companion Solid State Stoichiometry Activity learning object.

Evaluation Results: 

Most students have been able to determine the empirical formula for any of these structures. They sometimes struggle with the difference between a corner, an edge, a face, and inside the unit cell. Students are generally able to determine the stoichiometry for an extended solid that they have not previously seen.

Description: 

The page has JSmol structures for unic cells including cubic, body centered cubic, and face centered cubic unit cells as well as for CsCl, Ni3Al, Cu2O, NaCl, CaF2, ZnS, diamond, Li3Bi, NaTl, NiAl and ReO3The advanced page also has triclinic, monoclinic, hexagonal, orthorhombic, and tetragonal cells with all possible centering.

The purpose of this site is to help students visualize how much of an atom is in the unit cell so that compound stoichiometry can be determined. 

 

 
Corequisites: 
Prerequisites: 
Learning Goals: 

Students can determine the empirical formula from an extended solid state structure.

Students will be able to understand that a unit cell represents the contents of an extended solid.

Implementation Notes: 

We have used a physical model kit to build solid state structures in class for many years. After building a few structures, students often want to try some more structures. These online models were created to allow continued study and practice out of class.

Cubic unit cells are appropriate for an introductory course. The advanced unit cells include all crystal systems and centering options.

The display options "faces" and "perspective" are recommended for counting atoms within the cell. 

Time Required: 
1 hour
22 Jun 2016

Visualizing solid state structures using CrystalMaker generated COLLADA files

Submitted by Barbara Reisner, James Madison University
Evaluation Methods: 

I used the SALG (Student Assessment of Learning Gains) to see how much different aspects of the course help their learning. In 2015 (model kits only) and 2016 (model kits and Studio Viewer), I asked about the gains they made in understanding solid state structures. In 2016, I asked how much the model kits and Studio Viewer helped their learning.

Evaluation Results: 

On the end of semester SALG in 2016, I asked students about the solid state model kits and Studio Viewer. “HOW MUCH did each of the following aspects of the class HELP YOUR LEARNING?”

 Solid State Model KitsStudio Viewer
No help2%2%
A little help9%9%
Moderate help2%9%
Much help11%22%
Great help69%58%
Not Applicable2%2%

The students responded more favorably to the solid state model kits, but 80% of students thought that both the model kits and Studio Viewer provided much or great help.

I also asked, "As a result of your work in this class, what GAINS DID YOU MAKE in your UNDERSTANDING of each of the following?" Here are student responses for extended (solids) structure

 Spring 2016Studio Spring 2015
No gains2%-
A little gain7%10%
Moderate gain7%6%
Good gain36%41%
Great gain33%29%
Not Applicable-2%

As you can see, there are not great differences between the year I used Studio Viewer (Spring 2016) and the year I used only model kits.

I gave students the option of using it to help them complete an exam question and ~25% of my students used it on the exam. (Students who used the viewer were more likely to get the problem correct because using the viewer removed the ambiguity of where atoms in the unit cell could be found.)

Description: 

Although I’m a solid state chemist, I still find it difficult to teach the visualization of solid state structures. I’m interested in any tool that helps my students visualize solids. My experience is that the more representations students can master, the more likely they are to find one that helps them understand solid state structures.

I’ve used many tools. These include

  • plan diagrams
  • static 3D models (generated by CrystalMaker)
  • CrystalMaker files on a computer (I have a license for my laptop)
  • online sites like ChemTube3D
  • ICE Solid State Model Kits

I believe that it’s important to guide students as they explore 3D extended structures. Since there is no lab directly associated with my class, all of our visualization activities are done in a standard lecture room during one or more 50-minute class periods. While students can work with the free demo version of CrystalMaker on a computer, most students don’t bring their computers to class. However, most students have smartphones and tablets.

This activity describes how to generate DAE files (3D interchange file format). These files can be opened on student devices so that students can individually work with 3D models of extended solid state structures. 

Topics Covered: 
Corequisites: 
Prerequisites: 
Learning Goals: 

A student will be able to use alternate representations of extended solids to better visualize solid state structures.

Implementation Notes: 

I recommend that students download Studio Viewer and the Canvas (LMS) App before class. I also recommend that they practice getting files from Canvas to Studio Viewer before they come to class. (In the future, I will ask them to move all of these files to Studio Viewer prior to class.)

To streamline the transfer process, I make a single page that contains all of the DAE files so students only need to go to a single page on the LMS.

I’ve attached a few DAE files here. You can find many more with the associated LO, “A model for every student: Visualizing solid state structures”.

 

Time Required: 
Highly variable!
21 Jun 2016

A model for every student: Visualizing solid state structures

Submitted by Barbara Reisner, James Madison University
Evaluation Methods: 

I used the SALG (Student Assessment of Learning Gains) to see how much different aspects of the course help their learning. In 2015 (model kits only) and 2016 (model kits and Studio Viewer), I asked about the gains they made in understanding solid state structures. In 2016, I asked how much the model kits and Studio Viewer helped their learning.

Evaluation Results: 

On the end of semester SALG in 2016, I asked students about the solid state model kits and Studio Viewer. “HOW MUCH did each of the following aspects of the class HELP YOUR LEARNING?”

 Solid State Model KitsStudio Viewer
No help2%2%
A little help9%9%
Moderate help2%9%
Much help11%22%
Great help69%58%
Not Applicable2%2%

The students responded more favorably to the solid state model kits, but 80% of students thought that both the model kits and Studio Viewer provided much or great help.

When I asked students, "As a result of your work in this class, what GAINS DID YOU MAKE in your UNDERSTANDING of each of the following?" about extended (solids) structure, 69% of students reported making good or great gains and 7% reported making moderate gains. Only 2% reported making no gains.

 

Description: 

We do not cover extended solids (solid state materials) in our general chemistry program. With the exception of students who have taken a course in materials science, Inorganic Chemistry I is the first time our students have encountered solid state structure. Although they have built some visualization skills by working with molecules and symmetry, they do not have robust 3D visualization abilities and have trouble using the language of solid state chemistry (unit cells, packing, filling holes, coordination number, etc…) in the context of structure.

There are many excellent activities to help students develop these skills and I’ve customized an activity for my own class. I like having students use multiple representations, so we work with ICE Solid State Model Kits and DAE files (3D visualization that can be done on a smartphone or tablet device). I like using visualization tools that students can use individually so they can look at solids in a way that make sense to them.

The attached file is the activity that I work on with my students.  Students should complete this activity in groups during class time.

Learning Goals: 

A student will be able to…

  • use alternate representations of extended solids to better visualize solid state structures;
  • describe primitive / simple cubic (sc), hexagonal close packed (hcp), and cubic close packed (ccp) lattices in terms of packing and holes;
  • calculate the number of atoms in a unit cell and the stoichiometry of a solid;
  • calculate the coordination numbers of atoms and ions in solids;
  • draw plan diagrams;
  • determine the types of holes in sc, hcp, and ccp lattices;
  • use ionic radii to predict lattice (close packed) ions;
  • calculate the percentage of holes filled in solids.
Corequisites: 
Equipment needs: 

Students need smartphones or tablet devices. The DAE files also display on macs; they don’t display correctly on PCs. Students can share devices or use their own. I prefer that students use their own because they can manipulate the structure in the way that they want.

Topics Covered: 
Implementation Notes: 

I believe that it’s important to guide students as they explore 3D extended structures. Since there is no lab directly associated with my class, all of our visualization activities are done in a standard lecture room during one or more 50-minute class periods.

I have attached the in class activities that I walk through with my students. Students simultaneously look at the DAE files and models that they have built with ICE Solid State Model Kits. Building the solid state models takes time for inexperienced students, but many students appreciate being able to use in silicio and physical models. I frequently pause to emphasize important points, clarify what students should do, or to have a whole class discussion.

We are not able to make it through all of these activities during class, but after making it through the first 5 parts of this activity, students should have the skills needed to complete this on their own. This will take 3-4 class periods. I think that this activity could be done in a lab.

I collect worksheets at the end of every class to see how my students have progressed using the language of solid state chemistry.

Time Required: 
variable
16 May 2016

Metal and Ionic Lattices Guided Inquiry Worksheet

Submitted by Adam R. Johnson, Harvey Mudd College
Evaluation Methods: 

I walked through the classroom and guided the students as they worked in pairs or groups of three. All the answers were in prior assigned reading from their text so if they were confused, they had that to look at later.

Evaluation Results: 

Some students had trouble seeing some of the holes in the simple lattices, so it was helpful that I was walking around to show them the holes. It was good to have students work together becasue some students were able to see the holes in the geometries and help their partners.

Description: 

This is a short worksheet that guides students through simple metal lattices (SCP, CCP, HCP) and how filling holes in these lattices results in ionic lattices (NaCl, CsCl, fluorite, etc.).

The worksheet was used as an in-class activity after students had read about the material in the text. This activity is probably suitable for first-year students, though I used it with juniors/seniors.

Learning Goals: 

Students will be able to do the following:

for simple lattices:

draw the lattice

determine how many atoms per cell

determine the coordination number, CN, of an atom

locate common holes and describe their CN

calculate the % of space filled up by the atoms

 

For ionic solids:

draw the lattice and count the number of ions in the cell

relate to a simple lattice by hole-filling

determine the # and CN of both cations and anions

Equipment needs: 

none, though a box of pennies or marbles or ping pong balls might be helpful to visualize closest packing. Having models or computer models would have been helpful to show on a screen at the front of the room. rotatable cif files would be especially good, and next time I do this I will prepare cif files or crystalmaker files and upload them here.

Corequisites: 
Prerequisites: 
Implementation Notes: 

This was a bit too long for a 50-minute class period but students finished it up at home. The students who had spent the time reading the book before class definitely did better on the exercise than those who were clearly doing it for the first time in class. Students struggled a bit with the geometry/trig calculations.

Were I to do this again, I would have 3-d rotatable structures available (cif files or crystalmaker files) to help students with the visualization.

Time Required: 
1-1.5 50 minute class periods
15 May 2016

Introduction to Equilibrium and Aqueous Acids

Submitted by Adam R. Johnson, Harvey Mudd College
Evaluation Methods: 

the problems were evaluated electronically as a Sakai "quiz." Each question was graded right or wrong and added to the semester long homework score.

Description: 

Equilibrium reactions are those that are dynamic: the reaction can shift to form more reactants or more products depending on the physical or chemical conditions present. They were discovered and described empirically, but have a thermodynamic basis in the Gibbs Energy of the reaction. A reaction at equilibrium has both reactants and products present, and the rate of formation of products is equal to the rate of formation of reactants. A common application of equilibrium is the chemistry of aqueous acids. Acid strength is measured by the pH scale.

This unit could be a stand-alone unit, but I used it as the first day of a three-day series of in-class exercises designed to get students thinking about a real problem on the international space station that could be solved using equilibrium calculations.

Learning Goals: 

1.    Write the equilibrium constant expression from the law of mass action
2.    Predict the response of a reaction at equilibrium to an external “stress”
3.    Determine whether a given species is an acid or base
4.    Calculate the pH of a solution of a weak acid in water
5.    Write the chemical equation for the autoprotolyis of water
6.    Calculate the solubility of a sparingly soluble salt
 

Corequisites: 
Prerequisites: 
Equipment needs: 

none

Topics Covered: 
Course Level: 
Subdiscipline: 
Implementation Notes: 

This was the first day of a 3-day equilibrium activity. The 2nd two days are presented in the linked activity entitled "Water reclamation on the ISS: "Houston, we have a problem."

Students worked problems in class or as homework. For our class, the problems were submitted electronically on Sakai.

Time Required: 
1 50 minute class period
15 May 2016

Water reclamation on the ISS: “Houston, we have a problem.”

Submitted by Adam R. Johnson, Harvey Mudd College
Evaluation Methods: 

the exercises were evaluated according to the attached answer keys.

Evaluation Results: 

this ended up being a very difficult exercise, possibly more suited for sophomore or junior students. The students required some handholding to get through the exercises, but in the end, they seemed to understand that even seemingly simple aqueous systems are actually quite complicated. For Fall 2016, I intend to reframe and better stage this activity and possibly add in a discussion of EDTA as a complexing agent.

Description: 

Equilibrium reactions are those that are dynamic: the reaction can shift to form more reactants or more products depending on the physical or chemical conditions present. They were discovered and described empirically, but have a thermodynamic basis in the Gibbs Energy of the reaction. A reaction at equilibrium has both reactants and products present, and the rate of formation of products is equal to the rate of formation of reactants. A common application of equilibrium is the chemistry of aqueous acids. Acid strength is measured by the pH scale.

It costs approximately $10,000 per pound to ship supplies to the international space station in orbit around the earth. One way to minimize costs and provide additional life support options for the astronauts is to recycle wastewater back to drinkable water. Russia developed a dehumidifier type device that reclaimed moisture from the air from sweat and breathing, and this was used on the Mir space station in the 1990s. Scientists and Engineers at NASA developed a water reclamation device that improves overall water efficiency on the ISS by reclaiming water from urine. This unit was installed in 2009. However, the device is not working up to specifications and it is your job to figure out what is going wrong and make recommendations to improve it.

This activity was inspired by a conversation I had with Anne Jones from Arizona State at the VIPEr faculty development workshop at Northwestern in 2014.

Learning Goals: 

1.    Read and interpret tabular data
2.    Determine which precipitates might form from a complex mixture of ions
3.    Calculate the maximum solubility of a species in solution
4.    Determine the effect of acid/base chemistry on solubility

 

Equipment needs: 

none

Prerequisites: 
Corequisites: 
Course Level: 
Implementation Notes: 

This was done as a 2 day activity. The first day, students examine the speciation of various polyprotic ions in soluction and predict a precipitate. The second day, students look more closely at the chemical reactions carried out to purify water on the ISS and make a recommendation for an improved procedure.

There was originally going to be additional work involving EDTA complexation and formation constants, but the exercise was too long and this material was cut. However, consideration of the addition of EDTA would allow for a more sophisticated treatment.

This exercise is designed to show the effects of calcium leaching from bones by astronauts. This process is not completely understood, but blood concentrations of calcium are higher for astronauts. This led to a problem with the water purification system developed by NASA.

The keys for this exercise involve the solution of multiple simultaneous equations. This can be done using mathcad, mathmatica, or wolfram alpha. A link to a sample wolfram alpha solution is provided below.

Time Required: 
1 50 minute class period
15 May 2016

Energy Content of Fuels--Which fuel is "Best?"

Submitted by Adam R. Johnson, Harvey Mudd College
Evaluation Methods: 

the group assignments were graded according to the attached answer key.

Evaluation Results: 

I allowed any criteria to be used as that for determining the "best" fuel. One particularly cheeky group decided that their goal was to raise global temperatures to bring back environmental conditions for dinosaurs, because they wanted dinosaurs to come back. For the purposes of the assignment, this was a "correct" answer, given that they justified their desire to maximize CO2 emissions. However, most groups did determine that minimizing CO2 emissions is probably a better goal. The discussions I had with groups was generally very good while in class.

Description: 

There are many factors to consider when choosing a fuel. In this exercise, your group will work with a set of three different potential fuels and evaluate their performance in terms of price, energy density (per mole, per gram, and per volume) as well as in terms of CO2 emissions. You will then select which of your three fuels is the “best,” realizing that there are several possible considerations to select the “best” fuel. You will have to defend your choice, as well as your definition of “best!”

This is an activity that can stand alone, but I started with a lecture that outlined the major concepts of combustion, solar energy conversion, and catalysis. The slides I used are not mine, so I can not share them here, but I include an outline of the presentation as a guide.

I am indebted to VIPEr users Matt Whited and Karen Holman for discussions about developing and improving this activity. I am including them as co-authors on this activity for their help.

Learning Goals: 

1)    use Hess's Law to determine enthalpy changes associated with chemical reactions.
2)    use balanced chemical reactions, in combination with other relationships such as density, to derive other useful quantities related to a combustion reaction.
3)    identify trends in a set of related chemical reactions and note important characteristics of reactants and/or products that are related to or cause these trends.
4)    Account for for the many variables (chemical, societal, and political) associated with picking the "best" chemical fuels as well as for the ways in which their knowledge of thermochemistry and chemical reactions can be applied to understand these variables.
5)    Draw a reaction coordinate diagram showing the function of a catalyst in a chemical reaction, specifically showing:
a)    how one could limiting the combustion of methane to form methanol instead of CO2
b)    how one could maximize the storing solar energy in a fuel
 

Equipment needs: 

none, although demonstrating the combustion of isopropanol in a 5-L carboy is a good demo to do for the lecture. for example:

https://www.flinnsci.com/media/484580/95010-r.pdf

http://www.instructables.com/id/Woomf-Bottle-a.k.a-Fun-With-Fire/

Be mindful of safety doing this demo. Only bring a small amount of liquid fuel to do the demo (5-10 mL for a 4 L Erlenmeyer flask, and 20-30 mL for a 5 gallon carboy). The fire is reasonably self contained though it does jet upwards a few tens of inches to feet. It is a dramatic reminder/visual of thermodynamics and the quantity of energy that can be stored in chemical bonds.

Subdiscipline: 
Course Level: 
Corequisites: 
Prerequisites: 
Topics Covered: 
Implementation Notes: 

This module was used during the Fall of 2015 in a general chemistry class. I started with a lecture outlining the major considerations of energy and the storage of energy in chemical bonds. An outline for this presentation and several slides are provided.

in a second class period, students worked in groups to determine the "best" fuel. They were allowed to determine which criteria to use, as there really is not a right answer here. I had the students upload their data to a google spreadsheet (template is provided). This allowed the students to compare a number of fuels even if they only calculated 3 of them.

the final column in the table is price ($) per kJ of heat, but these values are so low it might be better to ask the students to report cents per J.

I did my best to find accurate values for the prices of the fuels. If people have better numbers, I would appreciate comments when you use the LO!

Time Required: 
2 50 minute class periods (1 with no lecture)
14 May 2016

soapmaking activity

Submitted by Adam R. Johnson, Harvey Mudd College
Evaluation Methods: 

the exercises were evaluated according to the keys provided

Description: 

This in-class activity is designed to follow the linked lecture/demonstration on soapmaking. The soaps cure enough to be handled in 48 hours if kept warm, and the students can feel the difference in the canola/coconut oil soaps.

The calcuations go through the major reactions, functional groups, and physical properties of soap molecules, and ends with the calculation of molecular weight for a mixture of substances. This could be related to a later polymer unit.

I include "Team Cards" so that some of the calculations are divided into a class dataset that could be presented in the last 5-10 minutes of class.

For 2016, I will have students do more of calculations, and then report back to the class on their results in a subsequent class period; there was not enough time for the reporting last year.

Learning Goals: 

1.    Identify the major functional groups found in soap and used in soapmaking
2.    Explain how soap works at the molecular level
3.    Draw balanced chemical reactions for the soapmaking process
4.    Calculate various metrics for soap and relate them to the soap’s properties
5.    Compare different ways of calculating the molecular weight of soap and polymers
 

Corequisites: 
Course Level: 
Equipment needs: 

none

Prerequisites: 
Related activities: 
Implementation Notes: 

the students struggled with the MW calculations and I would appreciate input on how to change this to help them understand it better.

Time Required: 
1 50 minute class period

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