Second year

17 Jan 2020

Formal oxidation states in Ru-catalyzed water oxidation

Submitted by Margaret Scheuermann, Western Washington University
Evaluation Methods: 

I did not grade this activity.

Evaluation Results: 

Three students out of 14 explicitly mentioned that this activity was helpful on the free response section of the course evaluations.

Description: 

This LO is an in-class assignment to prepare students for literature readings involving catalytic cycles in which multiple protons and electrons are transferred. Students practice assigning oxidation states to complexes with aquo, oxo, superoxo, and hydroperoxo ligands then use this information to analyze a proposed water oxidation mechanism from the literature.

Students are asked to add in the substrates and products entering and leaving the catalytic cycle. While this is, at its heart, a stoichiometry excercise, it helps calibrate students for the level of attention to detail needed to effectively engage with reading about multi-electron catalytic mechanisms.

Learning Goals: 

After completing this activity:

A student should be able to assign formal oxidation states to monometallic complexes with aquo, oxo, hyrdoperoxo, and superoxo ligands

A student should be able to apply their knowledge of formal oxidation states to the analysis of a proposed mechanism of a catalytic water oxidation reaction

Corequisites: 
Subdiscipline: 
Prerequisites: 
Implementation Notes: 

I used this activity during a lab lecture before an inorganic laboratory experiment in which students would be preparing and testing the Ru-based OEC mimic. 

I began the class period with a brief review of L/X type ligands and formal oxidation states. 

Students then worked in groups to complete this activity. 

 

Other implementation options:

While I used this activity as part of a lab lecture it could also be used in a lecture setting or as part of a problem set.

It could also be modified for use as an equation balancing excercise in a majors or honors general chemistry course.

Time Required: 
10-20 minutes
9 Jan 2020

Marvin suite from ChemAxon

Submitted by Anthony L. Fernandez, Merrimack College
Evaluation Methods: 

As my students draw structures, I usually observe them and make suggestions to improve their drawings. 

Evaluation Results: 

While I do no formal assessment of this activity, I have observed that students seem to learn how to use the program fairly quickly and then use it without much difficulty for the rest of the semester.

Description: 

It is important for students to be able to effectively communicate the results of their scientific work. This does not only inlcude written and oral communication, but the creation of appropriate representations of the complexes they have investigated. It is crucial that students learn how to draw molecules using electronic structure drawing programs, but site licenses for structure drawing programs can be prohibitive for some institutions.

Marvin suite is a software package from ChemAxon that is freely avaialble for educational institutions. It contains a structure drawing program (MarvinSketch) and a viewer (MarvinView), as well as tools that allow for the calculation of many molecular and spectroscopic properties of molecules. This is a very useful suite of programs that can be used by all students and faculty at an instituion once an Academic License is obtained.

A set of directions for drawing a coordination complex in MarvinSketch is also included as part of this learning object. These directions will guide the user as they draw the structure of a square-planar coordination complex, trans-[Ni(NCS)2(PMe3)2].

Corequisites: 
Prerequisites: 
Learning Goals: 

After following the instructions, students should be able to draw a chemical structure electronically using a chemical structure drawing program.

Once the structure in drawn in the program, a user would then be able to access the many other functions available in the software.

Implementation Notes: 

During the first week of our semester, lab sections are usually not held for courses so that student enrollment issues can be sorted out. In an advanced course such as Inorganic Chemistry, I want to take advantage of every week that I can so I use the first lab meeting time to have students learn how to use several software programs that they wil use over the course of the semester. 

I post the download link and the license file for the software on the course LMS before the lab period and I ask the students to download and install the software. You should make sure that students update their Java installation before installing the Marvin suite. (I also place a link to the Java download site on the course LMS as well, but students tend to ignore it.) Aside from the Java issue, I have found that there are no real issues encountered by students when they install the software. 

When we meet, I ask the students to follow the linked instructions to create a drawing of a coordination complex. Once they complete that successfully, I ask them to draw several other structures. I do not  have any specific structures that I use, but I try to choose complexes with different geometries (octahedral, tetrahedral, square pyramidal, etc.) around the metal center.

The Marvin suite of programs provides the students with a number of useful tools, not just a structure drawing progam. Students use this to calculate or estimate a number of different things, such as the molecular mass, the elemental analysis, a mass spectrum, 1H and 13C NMR, and charge distribution.

To obtain a license file, the faculty member must log into the ChemAxon site and request an Academic License. Once approved, the instituion is allowed to use the software for 2 years and the license can be easily renewed when it expires.

 

Time Required: 
30 minutes
8 Jan 2020

How to Read a Journal Article: Analyzing Author Roles and Article Components

Submitted by Catherine McCusker, East Tennessee State University
Evaluation Methods: 

Follow up small group work with a class discussion of the correct answers. Grade students on participation and completness

Description: 

This literature discussion uses a recently published article on solvatochromic Mo complexes to introduce students to the different components of a research article. The activity is divied into to two parts. Before class students read the paper and focus on defining terms, investigating the "meta" data of the paper, and the different sections iof the paper. In class the students work in groups to investigate the scientific content of the paper

Prerequisites: 
Course Level: 
Corequisites: 
Learning Goals: 

Students should be able to:

  • Interpret the roles that authors play in a research project
  • Recognize the different sections of a research article and the purpose of each section
  • Understand how to access supporting information and the type of information found there
  • Find key conclusions of a research paper and the experimental evidence the author used to make those conclusions
Time Required: 
~30 min (if students complete part 1 before class)
8 Jan 2020
Evaluation Methods: 

I usually grade one student handout per pair and typically have 1 pt per answer on the worksheet, but take the total out of 60 pts (which ends up giving them a couple of free points).  

Evaluation Results: 

Last semester my 17 students had an average of 47 out of 60 on the lab--a bit lower than usual for that lab. The high was a 57 and the low was a 39. There were lots of different individual errors, but errors in identifying which of the first structures were closest packed and errors in % of holes occupied were common. 

Description: 

This first-year laboratory is designed to give students an introduction to basic solid-state structures using both CrystalMaker files and physical models. I think this would work in a foundations level inorganic course as well. It could be used alternatively as an in-class activity or take-home problem set depending on the instructor. It was adapted by me and later, David Harvey, from an original activity that was posted as an educational resource on the CrystalMaker website in the mid 2000s.  

Prerequisites: 
Corequisites: 
Learning Goals: 

Students will be able to

  • articulate how the atoms in a simple cubic, face-centered cubic, and body-centered cubic unit cell are arranged
  • determine the coordination number of particular atoms in a unit cell
  • count the atoms or ions in a unit cell and determine the empirical formula based on that
  • determine the length of a side of a unit cell based on the radius of an atom
  • visualize the holes in different kinds of unit cells and see how ionic solids can be built by putting ions in those holes
  • describe the forces holding different solids together
  • calculate the % of filled and empty space in lattices
  • identify closest packed structures
Equipment needs: 
  • Computer lab (approximately two students per computer) with CrystalMaker installed (it can be the student version if necessary)

and/or

  • Box of pennies
  • Mineral samples of calcite, fluorite, and NaCl (if you want to do the bonus)
Implementation Notes: 

I usually take one day of class to introduce students to CrystalMaker and all of the basic definitions and ideas of this lab before they start working on the stations. Typically I will work through the first station and then part of NaCl to show them some of the main ideas they will be using, asking them to provide answers (which are typically wrong on the first try!). I am typically circulating around answering questions as the students work through the lab. For a lab section of 24 working in 12 pairs, having one set of physical models seems adequate, but particularly at the beginning of the lab it might be helpful to have two sets of the face-centered cubic and body-centered cubic structures. The 12 computer "stations" are arranged in folders inside a Solid State Lab folder on the desktop of the lab computers, so students can just click on the correct folder and correct files as they work their way through the lab.

Time Required: 
3h lab period
18 Oct 2019

Mechanisms of Mn-catalyzed water oxidation reactions

Submitted by Margaret Scheuermann, Western Washington University
Evaluation Methods: 

I did not grade this activity. 

Evaluation Results: 

Three students out of 14 explicitly mentioned that this activity was helpful on the free response section of the course evaluations.

 

Description: 

This LO is an in-class assignment to prepare students for literature readings involving catalytic cycles in which multiple protons and electrons are transferred. Two catalytic mechanisms, a proposed OEC mechanism and the proposed mechanism of a biomimetic OEC complexes are included. The intermediates are drawn including all charges and oxidation states, details which are sometimes omitted in the primary literature but can be helpful to students who are not accustomed to looking at multistep catalytic cycles. Students are then asked to add in the substrates and products entering and leaving the catalytic cycle. While this is, at its heart, a stoichiometry excercise, it helps calibrate students for the level of attention to detail needed to effectively engage with reading about bioinorganic catalytic mechanisms.

Learning Goals: 

After completing this activity:

A student will be able to follow along with each step in  proposed water oxidation mechanims in the literature.

A student will be able to apply their knowledge of stoichiomety to complex catalytic cycles involving electron transfer.

A student will be able to analyze and compare the details of catalytic cycles.

Corequisites: 
Subdiscipline: 
Prerequisites: 
Implementation Notes: 

I used this activity during a lab lecture before an inorganic laboratory experiment in which students would be preparing and testing an OEC mimic. The procedure we used was roughly based on a published procedure (J. Chem Ed. 2005, 82, 791) linked in web resources. 

I began the class period with a brief introduction to the chemistry of photosynthesis and where water oxidation and PSII fit in the broader picture. I then introduced the mimic that students would be preparing and the chemistry of the Oxone (R) triple salt. 

Students then worked in groups to complete this activity and discuss their structural and mechanistic observations. After the activity they were encouraged to read the papers referenced in the activity and to think about the evidence that supports the proposed mechanism.

 

Other implementation options:

While I used this activity as part of a lab lecture it could also be used to stimulate a discussion comparing structure/mechanism of biological and biomimetic systems in a lecture setting without the accompaning laboratory work.

This could also be modified for use as an equation balancing excercise in a majors or honors general chemistry course.

Time Required: 
10-20 minutes
9 Oct 2019

2019 Nobel Prize - Li-ion battery LOs

Submitted by Barbara Reisner, James Madison University

Congratulations to the 2019 recipients of the Nobel Prize - John B. Goodenough, M. Stan Whittingham and Akira Yoshino. It's a well deserved honor!

There are several LOs on VIPEr that talk about lithium ion batteries and related systems. The 2019 Nobel is a great opportunity to include something about these batteries in your class.

I hope to see more LOs in the coming weeks so we can bring this chemistry into our classrooms!

Prerequisites: 
Corequisites: 
8 Oct 2019
Evaluation Methods: 

assessment of students will be preformed by grading their answers to the questions in the activity.

Description: 

This is a 1 Figure lit discussion (1FLO) based on a Figure from a 2015 JACarticle on synthesizing conductive MOFs. This LO introduces students to Metal-Organic Frameworks and focuses on characterization techniques and spectroscopy. 

Prerequisites: 
Corequisites: 
Course Level: 
Learning Goals: 

As a result of completing this activity, students will be able to...

  • define what metal-organic Frameworks and Post-synthetic Modifications are
  • understand MOF terminology and notation
  • discover how mass transport and electron mobility effect conductivity
  • calculate energies of electronic transitions in electron volts
  • make connections betweeen diagrams and material sturctures
  • compare optical and microscopy techniques
  • discover the concept of photocurrect and how it could be used in different applications
Implementation Notes: 

Students should be able to complete the activity without any prior knowledge of MOFs, although some introduction to MOFs and UV-vis absorption spectroscopy would be nice.

29 Jul 2019

Introduction to Drago's ECW Acid-Base Model

Submitted by Colleen Partigianoni, Ferris State University
Description: 

This LO was created to introduce Drago’s ECW model, which is an important contribution to the discussion of Lewis acid-base interactions. Unlike the qualitative Pearson’s HSAB model (Hard Soft Acid-Base model,) the quantitative ECW model can be used to correlate and predict the enthalpies of adduct formation and to obtain enthalpy changes for displacement or exchange reactions involving many Lewis acids and bases.  Unlike all other acid-base models, graphical displays of the ECW model clearly show that there is no one order of acid or base strengths, and illustrate that two parameters are needed for each acid and base to provide an order of acid or base strength.  The ECW model can also provide a measure of steric strain energy or pi bonding stabilization energy accompanying adduct formation, which is not possible with any other acid-base model. 

This set of slides is intended to provide a basic introduction to the model and several examples of predicting energy changes using the model. It also illustrates how to construct and interpret a graphical display of the model.

 It should be noted that this LO is not in the PowerPoint format, but instead is a more extensive set of notes for instructors who are not familiar with the ECW model. It could be condensed and rewritten in the more standard PowerPoint format.

There is also an ECW problem set LO that can used to supplement this LO.

Prerequisites: 
Corequisites: 
Learning Goals: 

After viewing the slides, students, when provided with appropriate data, should be able to:

  • Calculate sigma bond strength in Lewis acid-base adducts using Drago’s ECW model.
  • Show how to deal with any constant energy contribution (W) to the reaction of a particular acid (or base) that is independent of the base (or acid) when an adduct is formed.
  • Garner information regarding steric effects and pi bond stabilization energy in Lewis acid-base adducts using the ECW model.
  • Show using a graphic display of ECW that two parameters for each acid and each base are needed in acid-base models to determine relative strengths of donors and acceptors.
Evaluation
Evaluation Methods: 

This LO has not been used yet and evaluation information will be posted at a later date.

25 Jul 2019

1FLO: One Figure Learning Objects

Submitted by Chip Nataro, Lafayette College
Corequisites: 
18 Jul 2019

Science Information Literacy Badge--Reading the Literature

Submitted by Michelle Personick, Wesleyan University
Evaluation Methods: 

I use this activity as a "badge," which is self-paced guided skill-building activity that students complete on their own time outside of class. Badges are designed around fundamental chemistry skills that students wouldn’t necessarily acquire from standard course content and lectures. They carry a very small point value (about 2% of the course total per badge) but my students are very motivated by even small amounts of points. I assign points primarily based on completion and effort and also provide brief written feedback for each student. I have my students turn in badges in Moodle, which makes feedback more streamlined.

Description: 

This is an activity designed to introduce general chemistry students to reading the chemistry literature by familiarizing them with the structure of a published article. The activity first presents an article from the Whitesides group at Harvard about writing a scientific manuscript, along with a video about the peer-review process. There are two parts to the questions in the activity, which are based on a specific article from Nature Communications (doi.org/10.1038/s41467-019-08824-8). Part I is focused on the structure of the article and where to find key pieces of information. Part II encourages students to use general audience summaries in combination with the original article to best understand the science while making sure they get a complete and accurate picture of the reported work.

Prerequisites: 
Course Level: 
Corequisites: 
Learning Goals: 

A student should be able to approach the chemistry literature and determine where to find:

  • the authors and their affiliations;
  • the main objective of the research;
  • the main outcomes of the research;
  • why the research is important;
  • experimental details;
  • supplementary figures and other information. 

A student should be able to broadly evaluate the reliability of secondary summaries of scientific articles by comparing them against the key points of the original paper.

Implementation Notes: 

This activity is based on a specific article: "Room temperature CO2 reduction to solid carbon species on liquid metals featuring atomically thin ceria interfaces" (Nat. Commun., 2019, 10, 865. doi.org/10.1038/s41467-019-08824-8). However, it's easily adapted to other articles that are more suited to a particular course, and I've used other articles in previous iterations. This article was chosen because the content is at least partly accessible to students in my second semester general chemistry course, who have already had some electrochemistry/redox chemistry, and who have recently learned about kinetics, reaction mechanisms, and catalysis. The topic of liquid metals is new and interesting to the students, because it's not something the'd normally be exposed to, and the application to CO2 sequestration is something they can connect with. 

 

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