Periodic trends

1 Jun 2018
Evaluation Methods: 

This LO has not been implemented; however, we recommend a few options for evaluating student learning:

  • implement as in-class group work, collect and grade all questions

  • have students complete the literature discussion questions before lecture, then ask them to modify their answers in another pen color as the in-class discussion goes through each questions

  • hold a discussion lecture for the literature questions; then for the following lecture period begin class with a quiz that uses a slightly modified problem.

Evaluation Results: 

This LO has not been implemented yet.

Description: 

In honor of Professor Richard Andersen’s 75th birthday, a small group of IONiC leaders submitted a paper to a special issue of Dalton Transactions about Andersen’s love of teaching with the chemical literature. To accompany the paper, this literature discussion learning object, based on one of Andersen’s recent publications in Dalton, was created. The paper examines an ytterbium-catalyzed isomerization reaction. It uses experimental and computational evidence to support a proton-transfer to a cyclopentadienyl ring mechanism versus an electron-transfer mechanism, which might have seemed more likely.

 

The paper is quite complex, but this learning object focuses on simpler ideas like electron counting and reaction coordinate diagrams. To aid beginning students, we have found it helpful to highlight the parts of the paper that relate to the reading questions. For copyright reasons, we cannot provide the highlighted paper here, but we have included instructions on which sections to highlight if you wish to do that.

 

Corequisites: 
Course Level: 
Learning Goals: 

After completing this literature discussion, students should be able to

  • Count the valence electrons in a lanthanide complex

  • Explain the difference between a stoichiometric and catalytic reaction

  • Predict common alkaline earth and lanthanide oxidation states based on ground state electron configurations  

  • Describe how negative evidence can be used to support or contradict a hypothesis   

  • Describe the energy changes involved in making and breaking bonds

  • On a reaction coordinate diagram, explain the difference between an intermediate and a transition state

  • Explain how calculated reaction coordinate energy diagrams can be used to make mechanistic arguments

Implementation Notes: 

This is a paper that is rich in detail and material. As such, an undergraduate might find it intimidating to pick up and read. We have provided a suggested reading guide that presents certain sections of the paper for the students to read. We suggest the instructor highlight the following sections before providing the paper to the students. While students are certainly encouraged to read the entire paper, this LO will focus on the highlighted sections.  

 

Introduction

            Paragraph 1

            Paragraph 2

            Paragraph 3

            Paragraph 4

First 5 lines ending at the word high (you may encourage students to look up exergonic if that is not a term commonly used in your department)

Line 14 starting with “In that sense,” through the end of the paragraph

            Paragraph 6

From the start through the word “endoergic” in line 22

Line 31 from “oxidation of” to the word “described” in line 33

Line 40 from “These” to the word “dimethylacetylene” in line 45

Paragraph 7

            From the start to the word “appears” in line 4

            The words “to involve” in line 4

            Starting in line 4 with “a Cp*” to “transfer” in line 5

Results and Discussion

            Paragraph 1

            Paragraph 2

            Paragraph 3 from the start through “six hours” in line 10

            Paragraph 4

            Paragraph 5

                        From the start to “solution” in line 3

                        From “This exchange” in line 10 to “allene” in line 11

                        From “Hence” in line 19 through the end of the paragraph

            Paragraph 6 from the start through “infrared spectra” in line 19

            Paragraph 7 from “Hence” in line 4 through the end of the paragraph

Mechanistic aspects for the catalytic isomerisation reaction of buta-1,2-diene to but-2-yne using (Me5C5)2Yb p 2579.

            Paragraph 1

            Paragraph 2

            Paragraph 3

            Paragraph 4

Experimental Section

            Synthesis of (Me5C5)2Yb(η2-MeC≡CMe).

            Synthesis of (Me5C5)2Ca(η2-MeC≡CMe).

Reaction of (Me5C5)2Yb with buta-1,2-diene

 

 

 

Time Required: 
One class period.
3 Jun 2017

Literature Discussion of "A stable compound of helium and sodium at high pressure"

Submitted by Katherine Nicole Crowder, University of Mary Washington
Evaluation Methods: 

Students could be evaluated based on their participation in the in-class discussion or on their submitted written answers to assigned questions.

Evaluation Results: 

This LO has not been used in a class at this point. Evaluation results will be uploaded as it is used (by Spring 2018 at the latest).

Description: 

This paper describes the synthesis of a stable compound of sodium and helium at very high pressures. The paper uses computational methods to predict likely compounds with helium, then describe a synthetic protocol to make the thermodynamically favored Na2He compound. The compound has a fluorite structure and is an electride with the delocalization of 2e- into the structure.

This paper would be appropriate after discussion of solid state structures and band theory.

The questions are divided into categories and have a wide range of levels.

Dong, X.; Oganov, A. R.; Goncharov, A. F.; Stavrou, E.; Lobanov, S.; Saleh, G.; Qian, G.-R.; Zhu, Q.; Gatti, C.; Deringer, V. L.; et al. A stable compound of helium and sodium at high pressure. Nature Chemistry 2017, 9 (5), 440–445 DOI: 10.1038/nchem.2716.

Corequisites: 
Learning Goals: 

After reading and discussing this paper, students will be able to

  • Describe the solid state structure of a novel compound using their knowledge of unit cells and ionic crystals
  • Apply band theory to a specific material
  • Describe how XRD is used to determine solid state structure
  • Describe the bonding in an electride structure
  • Apply periodic trends to compare/explain reactivity
Implementation Notes: 

The questions are divided into categories (comprehensive questions, atomic and molecular properties, solid state structure, electronic structure and other topics) that may or may not be appropriate for your class. To cover all of the questions, you will probably need at least two class periods. Adapt the assignment as you see fit.

CrystalMaker software can be used to visualize the compound. ICE model kits can also be used to build the compound using the template for a Heusler alloy.

Time Required: 
2 class periods
3 Jun 2017
Evaluation Methods: 

This learning object was created at the pre-MARM workshop in 2017 and as such has not been used in a classroom setting. The authors will update the learning object once they have used it in their classes.

Description: 

This module offers students in an introductory chemistry or foundational inorganic course exposure to recent literature. Students will apply their knowledge of Lewis dot structure theory and basic thermodynamics to compare and contrast bonding in SiO2 and CO2.

Corequisites: 
Course Level: 
Prerequisites: 
Learning Goals: 

Students should be able to:

  1. Describe the bonding in SiO2 and related compounds (CO2)

  2. Use Lewis dot structure theory to predict bond orders

  3. Apply bonding models to compare and contrast bond types and bond energies (sigma, pi)

  4. Characterize bond strengths based on ligand donors

Implementation Notes: 

Students should read the first paragraph of the paper prior to completing this learning object. They can be encouraged to read more of the paper, but the opening paragraph is the focus of this learning object.

Time Required: 
50 min
18 Jan 2017

calistry calculators

Submitted by Adam R. Johnson, Harvey Mudd College
Description: 

I just stumbled on this site while refreshing myself on the use of Slater's rules for calculating Zeff for electrons. There are a variety of calculators on there including some for visualizing lattice planes and diffraction, equilibrium, pH and pKa, equation balancing, Born-Landé, radioactive decay, wavelengths, electronegativities, Curie Law, solution preparation crystal field stabilization energy, and more.

I checked and it calculated Zeff correctly but I can't vouch for the accuracy of any of the other calculators. 

Prerequisites: 
Corequisites: 
Learning Goals: 

This is not a good teaching website but would be good for double checking math

 

Implementation Notes: 

I used this to double check my Slater's rules calculations (and found a mistake in my answer key!)

11 Jan 2017

Group VI metal carbonyl compounds with pincer ligands

Submitted by Chip Nataro, Lafayette College
Evaluation Methods: 

This was developed after the semester in which I teach this material. I look forward to using it next fall and I hope to post some evaluation data at that point.

Description: 

This literature discussion is based on a short paper describing a series of Group VI metal carbonyl compounds that have pincer ligands (Organometallics, 201635, 229). While the paper is relatively straightforward, there are many subtle points that can be brought out by asking the right questions which hopefully this LO does. Some of the questions the students should be able to answer directly from the paper. I feel it is important that they do this. However, these questions nicely set up further questions that require the students to go beyond what is covered in the paper. In addition to the synthesis, there are many questions related to the spectroscopic characterization of these compounds. And of course, it wouldn't be one of my LOs if students weren't being asked to count electrons and do group theory.

Corequisites: 
Prerequisites: 
Learning Goals: 

Upon completing this LO students should be able to

  1. Use the CBC method to count electrons in the tungsten compounds in this paper
  2. Describe the bonding interaction between a metal and a terminal carbonyl ligand
  3. Explain how NMR can be used to characterize these compounds including a discussion of 183W satellites
  4. Relate data from IR spectroscopy to the bonding interaction between a metal and a ligand and describe how the IR data can provide information about the electron donor ability of related ligands
  5. Recognize that some observed trends just do not have good explanations
 
Course Level: 
Implementation Notes: 

This might be a bit on the long side, you could certainly omit some of the questions or have the students work on it outside of class.

Time Required: 
50 minutes or so
4 Jan 2017
Description: 

This is a great new textbook by George Luther III from the University of Delaware.  The textbook represents the results of a course he has taught for graduate students in chemical oceanography, geochemistry and related disciplines.  It is clear that the point of the book is to provide students with the core material from inorganic chemistry that they will  need to explain inorganic processes in the environment.  However the material is presented in such a clear, logical fashion and builds so directly on fundamental principles of physical inorganic chemistry that the book is actually applicable to a much broader audience.  It provides a very welcome presentation of frontier orbital theory as a guide to predicting and explaining much inorganic chemical reactivity.  There are numerous very  helpful charts and tables and diagrams.  I found myself using the book for a table of effective nuclear charges when I was teaching general chemistry last semester.  The examples are much more interesting that the typical textbook examples and would be easy to embellish and structure a course around.  There is also a helpful companion website that provides powerpoint slides, student exercises and answers.  The book covers some topics not typically seen in inorganic textbooks like the acidity of solids but the presentation of this information makes sense in light of the coherent framework of the text.  We so often tell our students "structure dictates function".  This text really make good on that promise.  My only complaint is that I wish the title were something more generic so that I could use it for a second semester of introductory-esque material that we teach after students have taken a single semester of intro chem and two semesters of organic chemistry.  So much of what is covered in this textbook is precisely what a second semester sophomore chemistry major should know before proceeding on in the major.  But the title makes the book hard to sell to chemistry majors and that is regrettable. 

Prerequisites: 
Course Level: 
29 Dec 2016

The Monsanto acetic acid process

Submitted by Chip Nataro, Lafayette College
Evaluation Methods: 

This was developed after the semester in which I teach this material. I look forward to using it next fall and I hope to post some evaluation data at that point.

Description: 

This literature discussion is based on one of early papers detailing the mechanism for the Monsanto acetic acid process (J. Am. Chem. Soc., 1976, 98, 846). In this communicaiton the identification of key intermediates in this process is carried out using infrared spectroscopy. While the paper is an easy read, there are lots of subtle points that can be brought out by asking the right questions which hopefully this LO does. Although we have plenty of excellent LOs asking students to identify the individual steps in the catalytic mechanism, this LO takes a slightly different approach and marches students through the mechanism.

Course Level: 
Prerequisites: 
Corequisites: 
Subdiscipline: 
Learning Goals: 

Upon completing this LO students should be able to

  1. Use the CBC method to count electrons in the rhodium compounds in this paper
  2. Describe the bonding interaction between a metal and a terminal carbonyl ligand
  3. Identify the various reactions taking place in the Monsanto acetic acid process
  4. Relate data from IR spectroscopy to the bonding interaction between a metal and a ligand and to the identification of intermediates in this process
Time Required: 
50 minutes or so

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