First Semester Inorganic Chemistry / Foundation Course in Inorganic Chemistry

19 May 2020

MO diagram for square planar methane guided inquiry

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

Since this is done in class, it is not graded. Since I correct their mistakes in real time, the final MO diagram is usualy almost perfect.

Evaluation Results: 

Students often want to have the electrons in the LGOs 'ride over' on the non-bonding MO instead of falling down to the lowest energy bonding MO. After pointing it out several times in class, students are generally better at using the aufbau principle.

Description: 

This guided inquiry activity takes students through the process of constructing an MO diagram for square planar methane. LGOs are constructed using a graphical approach. Students are guided through a process that allows them to use their MO diagram to make a claim about chemical properties.

Learning Goals: 

Students will derive the LGOs for methane in the D4h point group.

Students will derive the MO diagram for methane in the D4h point group.

Corequisites: 
Course Level: 
Equipment needs: 

none

Implementation Notes: 

This would come after spending several class periods developing LGOs for polyatomics.

I use this method (though not this detailed worksheet) every year in class. I have students divide up into teams and work together at the chalkboard on molecules like borane, methane, water, SF4, and others. I circulate through the class and correct their diagrams in real time. Then at the end, each team presents their MO diagram and its major features.

Time Required: 
30 minutes
19 May 2020

MO diagram for water guided inquiry

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

Since this is done in class, it is not graded. Since I correct their mistakes in real time, the final MO diagram is usualy almost perfect.

Evaluation Results: 

Students don't know which orbitals to mix to form MOs at first and need guidance.

Students don't really understand the concept of hybrid orbitals within the framework of MO theory until they see a few examples.

 

Description: 

This guided inquiry activity takes the students through the whole process of constructing an MO diagram for water in detail. The LGOs are constructed using my graphical approach (linked below) and hybrid orbital formation is discussed. Along the way, students are given hints on what to think about when constructing an MO diagram.

Learning Goals: 

Students will derive the LGOs for water.

Students will derive the MO diagram for water without sp mixing.

Students will derive the MO diagram for water with sp mixing.

 

Corequisites: 
Course Level: 
Equipment needs: 

none

Implementation Notes: 

This would come after spending several class periods developing LGOs for polyatomics.

I use this method (though not this detailed worksheet) every year in class. I have students divide up into teams and work together at the chalkboard on molecules like borane, methane, water, SF4, and others. I circulate through the class and correct their diagrams in real time. Then at the end, each team presents their MO diagram and its major features.

Time Required: 
30 minutes
18 May 2020
Evaluation Methods: 

I have not yet implemented this LO. As with other literature discussions, instructors could collect the completed worksheets (by an individual student or in groups of students) for evaluation.

Evaluation Results: 

I have not yet implemented this LO so there are currently no evaluation results to share.

 

 

Description: 

This literature discussion focuses upon the Science article by Coates and Waymouth reporting the synthesis of thermoplastic elastomeric polypropylene by an unbridged zirconocene. This article was the basis for the work done for my PhD thesis in the Waymouth group. The LO was written in May 2020 in honor of Bob Waymouth's 60th birthday. See the BITeS post announcing the LO here

Course Level: 
Corequisites: 
Subdiscipline: 
Learning Goals: 

After completing this literature discussion, students will be able to:

  • describe a thermoplastic elastomer
  • describe the stereochemistry of polypropylene
  • describe the relationship between catalyst structure and polypropylene stereochemistry
  • apply covalent bond classification electron counting to a zirconocene
  • interpret data from figures and tables
  • describe the methods used by the authors to support the synthesis of isotactic-atactic stereoblock polypropylene
Implementation Notes: 

As usual, instructors may wish to mix-and-match questions to suit their learning goals and time constraints.

This article addresses a part of the ACS list of inorganic chemistry macromolecular, supramolecular and nanoscale (MSN) topics:

  • Ziegler-Natta, metallocene catalysts for olefin polymerization - impact on industrial/materials development
Time Required: 
depends upon implementation; minimum of 20-30 minutes for the literature discussion if students read and answer questions outside of class
29 Apr 2020

How to write a (good) paper

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

This came through my twitter feed today and I thought I would share. I'm linking to McNeil's "Resources" page which has a lot of useful info, but I am specifically talking about the "How to Write a Paper" pdf docuemnt that came from her group taking a few group meetings to discuss what made a good paper. I think this is definitely someting I will keep in mind as I work on my writing this summer!

This pdf gives examples of both good and bad, as well as what her group though about as they made up this resources. It includes secions on titles, abstracts, TOC graphics, introductions, R&D, conclusions, and chemdraw, as well as things to consider for ESI.

 

Topics Covered: 
Course Level: 
Corequisites: 
Learning Goals: 

A student will learn what a real live research group thought about putting together a manuscript, and see some useful tips and pointers for assembling thier own manuscript or report.

Implementation Notes: 

I intend to share this with my summer research studnets and thesis students. Especially as we are moving into a writing phase of research here in summer 2020.

21 Mar 2020

Ferrocene acylation - The Covid-19 Version

Submitted by Chip Nataro, Lafayette College
Description: 

This is the classic Chromatography of Ferrocene Derivatives experiment from "Synthesis and Technique in Inorganic Chemistry" 3rd Ed. (1986 pp 157-168) by R. J. Angelici. There are no significant changes from the experiment published in the book so details will not be provided. What is provided are links to some excellent videos showing the experiment and characterization data for students to work with. For the time being this will be a living document. Currently it has 1H, 13C{1H}, COSY, DEPT, HMBC, HSQC IR, UV-Vis, GC-MS and Cyclic Voltammetry raw data files for all compounds for students to work with. It also includes processed 1H, 13C{1H}, COSY, DEPT, HMBC, HSQC, IR, GC-MS and Cyclic Voltammetry data for all compounds. If anyone has any additional means of characterization they would like to include (say Mossbauer) please feel free to contact the author.

Corequisites: 
Learning Goals: 

A student should get an appreciation for what doing this lab would be like by watching videos. In addition, the student will analyze the data provided and learn about the characterization of ferrocene, acetylferrocene and 1,1'-diacetylferrocene.

Equipment needs: 

Nothing.

The NMR data comes from a Bruker instrument and can be opened with TopSpin, MestReNova and perhaps other programs.

Implementation Notes: 

Like most everyone at this time this is going to be a trial by fire.

20 Mar 2020

setting up an air-sensitive reaction (video)

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

have not done

Evaluation Results: 

n/a

Description: 

This is a video I made to demonstrate the basics of air-sensitive reaction setup under nitrogen flush. It is the simplest, most basic method for setting up a reaction with air/water sensitive reagents.

The link goes to my channel on YouTube.

Corequisites: 
Subdiscipline: 
Learning Goals: 

After watching this video, a student will be able to set up a reaction under nitrogen. Or, if there is a global pandemic and the students are at home, they will at least see how it is done.

Course Level: 
Implementation Notes: 

I made this and am sharing it with my students because they did not get an opportunity to set up an air sensitive reaction this year.

Time Required: 
5 minutes to watch video
9 Oct 2019

Fourier Transform IR Spectroscopy of Tetrahedral Borate Ions

Submitted by Zachary Tonzetich, University of Texas at San Antonio
Evaluation Methods: 

The students perpare laboratory reports displaying their data in proper format with each peak labeled. The report must also contain answers to all of the quetions posed in the manual. Student performance and learning is assessed by the qualtity of their written reports and by a separate quiz covering aspects of vibrational spectroscopy. Teaching assistans also ensure that students' data acquisition is performed in a satisfactory manner during the laboratory period.

Evaluation Results: 

Students typically have great difficulty connecting the idea of normal modes, their symmetries, and why we observe IR peaks. They approach IR spectroscopy in much the same way they do NMR spectroscopy (i.e. methane shows four equivalent C-H bonds so I expect one C-H stretching motion) leading to serious misconceptions. This laboratory was designed in part to dispell these misconceptions. Question 1 addresses this issue most directly and many of the class answer incorrectly.

The questions in the laboratory involving harmonic oscialltor analysis are generally more straightforward for students as they just need to use the correct equations. Most of the class answers these correctly.

Likewise, students generally understand that vibrational frequencies are inversely proportional to the mass of the atoms involved in the vibration and are there able to make connections between the observed spectra of BH4-, BD4- and BF4-.

Aspects of functional group analysis are more familiar to students and they generally have little trouble assigning the spectrum of tetraphenylborate.

Description: 

This experiment was developed for an upper division Instrumental Analysis course to give students additional experience with infrared (IR) spectroscopy beyond the routine functional group identification encountered in undergraduate Organic Chemistry courses. It shares some aspects with the analysis of gas phase rovibrational spectra typically performed in Physical Chemistry courses, but places a greater emphasis on more practical considerations including data acquisition (using ATR) and interpretation. The molecular ions used in the experiment also demonstrate tetrahedral symmmetry which allows for topics in Group Theory to be exploited.

The experiment has students record the spectra of several tetrahedral borate ions including the isotopomers NaBH4 and NaBD4. The students then analyze their data in the context of the symmetry of normal modes, the harmonic osciallator model, comparisons with Raman spectra, and functional group composition. Post lab questions guide students through each of the topics and ask them to make quantative and qualitative predictions based on their data and theoretical models of molecular vibration.

Course Level: 
Learning Goals: 

-Students should be able to understand the relationship between molecular structure, normal modes, and peaks in the IR spectrum. This is a major misconception with students as they tend to believe that the presence of four B-H bonds in the borohydride ion will neccessary mean that four peaks (or one since they are equivalent) will be observed by IR. Unlike NMR spectroscopy, there is no 1:1 correspondence between the number of equivalent bonds and the number of peaks observed in the spectrum.

-Students should also be able to apply their knowledge of theoretical models (quantum harmonic oscillator) to quantitaively intrepret IR spectra and predict the energy of transitions that cannot be observed due to instrumental limitations.

-Students should be able to understand at a qualitative level how the masses of atoms affect the energy of molecular vibrations.

Equipment needs: 

The only required piece of equipment beyond the chemicals is an infrared spectrophotometer. At our institution we use an ATR element to acquire the data, but KBr pellets or nujol mulls should work equally well. All chemicals were purchased from Sigma-Aldrich and are of reasonable price.

Implementation Notes: 

See attached file with more details. The data acquisition is very straightforward if ATR sampling is employed. Students need only use the instrument for about 15 - 20 minutes to record all four samples.

Time Required: 
30 minutes to 2 hr depending upon the number of students.
25 Jul 2019

1FLO: One Figure Learning Objects

Submitted by Chip Nataro, Lafayette College
Corequisites: 
27 Jun 2019

Porphyrin-Based Metal-Organic Frameworks

Submitted by Amanda Bowman, Colorado College
Evaluation Methods: 

Students completed this activity in small groups, then turned in individual worksheets. Student learning and performance were assessed through 1) in-class group discussion after they had worked on the activity in small groups, and 2) grading the individual worksheets. Participation was most important in the small-group portion.

Evaluation Results: 

In general, students really enjoyed this exercise and felt that it was helpful for visualizing metal-organic frameworks (particularly the extended 3D structure). They also generally felt that it was helpful in visualizing the bonding sites of metal vertices, particularly for thinking about how that influences potential reactivity. We used Mercury as a visualization software for this discussion, and the majority of students felt very comfortable using Mercury and looking at cifs on their own after this activity.

 

The biggest challenge for students seemed to be in relating the 3D structure in the cif to the images and chemicals formulas in the article. They also tended to need some hints about question 5 – to think about what information Mössbauer can provide about oxidation state of the metal, or that you can tell whether or not there are two distinct iron environments. In our class, we do brief units on X-ray crystallography including how to use and interpret cifs, and Mössbauer spectroscopy before this literature discussion. If those topics are not already addressed in a particular class it might be helpful to add them in or directly address those topics for the students as an introduction to the literature discussion.

Description: 

This literature discussion explores the physical structures, electronic structures, and spectroscopic characterization of several porphyrin-based metal-organic frameworks through discussion of “Iron and Porphyrin Metal−Organic Frameworks: Insight into Structural Diversity, Stability, and Porosity,” Fateeva et al. Cryst. Growth Des. 2015, 15, 1819-1826, http://dx.doi.org/doi:10.1021/cg501855k. The activity gives students experience visualizing and interpreting MOF structures, and gives students exposure to some of the methods used to characterize MOFs.

Corequisites: 
Course Level: 
Learning Goals: 

Students will be able to:

  • Interpret and describe the bonding and structural characteristics of MOFs
  • Apply knowledge of ligand field strength to electronic structure of MOFs
  • Analyze X-ray crystallographic data to gain information about structural characteristics of MOFs
  • Interpret Mössbauer spectra to gain information about electronic structure of MOFs
Implementation Notes: 

This literature discussion was designed for use in an advanced (upper-level) inorganic chemistry course, but could be used in a foundational inorganic course if students have already been introduced to d-splitting diagrams and are given some coverage of Mössbauer spectroscopy and X-ray crystallography. When covering MOFs in class, students frequently expressed that visualizing and understanding the bonding sites and extended 3D structures was very challenging. So, this literature discussion was developed specifically to address that. Students completed this activity in small groups. It is very helpful to advise students ahead of time to bring laptops (or instructor should have some available) and to have the cifs from the paper downloaded and ready to go. We used Mercury as a visualization software for this activity. This activity can easily be completed in one class period. It is also helpful if students have been provided with the article ahead of time and encouraged to look it over – otherwise the most time-consuming part of this activity was allowing time for students to examine the MOF structure images in the paper before being able to discuss and answer the questions with their groups.

Note on visualization of MOFs using Mercury: To answer the discussion questions, we used the ‘stick’ or the ‘ball and stick’ style. We also used the default packing scheme (0.4x0.4x0.4) and the 1x1x1 packing scheme. The packing scheme can be changed by selecting Packing/Slicing… in the Calculate menu. I also had students view the 3x3x3 packing scheme – while this is not necessary to answer the discussion questions, it was interesting for students to be able to visualize the extended structure of the MOFs.

 

9 Jun 2019

Chem 165 2018

Submitted by Adam R. Johnson, Harvey Mudd College

This is a collection of LOs that I used to teach a junior-senior seminar course on organometallics during Fall 2018 at Harvey Mudd College. There were a total of 9 students in the course. The Junior student (there was only one this year) was taking 2nd semester organic concurrently and had not takein inorganic (as is typical).

Subdiscipline: 
Corequisites: 
Course Level: 

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