VIPEr

An ion exchange method to produce metastable wurtzite metal sulfide nanocrystals

Course Level:

Corequisites:

Prerequisites:

Topics Covered:

Related activities:

Visualizing solid state structures using CrystalMaker generated COLLADA files

Solid State Models with ICE Solid State Model Kits

Solid State Stoichiometry Online

X-ray Crystallography

Close Packing Activity

Introduction to Miller Indices

Implementation Notes:

This learning object was developed at the 2017 MARM IONiC workshop on VIPEr and Literature Discussions. It has not yet been implemented.

This could be assigned for homework, but would likely work better in class with guidance.

Time Required:

This will probably take 50 minutes depending on how much work with models you do.

Web Resources:

J. Am. Chem. Soc. 2016, 138, 471-474

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

Additional Authors:

Nicholas A. Piro, Albright College

Rebecca M. Jones, George Mason University

William G Dougherty, Susquehanna University

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:

Course Level:

Topics Covered:

Physical properties

Synthesis and reactivity

Prerequisites:

No Prerequisites

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

Subdiscipline:

Metal - Noble Gas Bonding

Related activities:

Solid State Models with ICE Solid State Model Kits

Looking at Solid State Structures

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

Web Resources:

A stable compound of helium and sodium at high pressure

ICE Solid State Model Kits

3 Jun 2017

An ion exchange method to produce metastable wurtzite metal sulfide nanocrystals

Submitted by Janet Schrenk, University of Massachusetts Lowell

Additional Authors:

Barbara Reisner, James Madison University

Catherine McCusker, East Tennessee State University

Eric Villa, Creighton University

Meng Zhou, Lawrence Technological University

Evaluation Methods:

Evaluation methods are at the discretion of the instructor. For example, you may ask students to provide written answers to the questions, evaluate whether they participated in class discussion, or ask students to present their answers to specific questions to the class.

Description:

In this literature discussion, students use a paper from the literature to explore the synthesis, structure, characterization (powder XRD, EDS and TEM) and energetics associated with the production of a metastable wurtzite CoS phase. Students also are asked define key terms and acronyms used in the paper; identify the goal of the experiments and determine if the authors met their goal. They examine the fundamental concepts around the key crystal structures available.

Preserving Both Anion and Cation Sublattice Features during a Nanocrystal Cation-Exchange Reaction: Synthesis of a Metastable Wurtzite-Type CoS and MnS

Powell, A.E., Hodges J.M., Schaak, R.E. J. Am. Chem. Soc. 2016, 138, 471-474.

http://pubs.acs.org/doi/abs/10.1021/jacs.5b10624

There is an in class activitiy specifically written for this paper.

Corequisites:

Course Level:

Topics Covered:

Electronic spectroscopy

Extended structure

Kinetics

Reaction mechanisms

Synthesis and reactivity

Prerequisites:

Learning Goals:

In answering these questions, a student will be able to…

define important scientific terms and acronyms associated with the paper;
describe the rocksalt, NiAs, wurtzite, and zinc blende in terms of anion packing and cation coordination;
differentiate between the structure types described in the paper;
explain the difference between thermodynamically stable and metastable phases and relate it to a free energy diagram; and
describe the structural and composition information obtained from EDS, powder XRD, and TEM experiments.

Subdiscipline:

Nanochemistry

Investigating the structures of close packed solids in metal sulfide nanocrystals

Related activities:

Thinking about Mechanisms of Metal Ion Exchange

Solid State Models with ICE Solid State Model Kits

Visualizing solid state structures using CrystalMaker generated COLLADA files

Solid State Stoichiometry Online

X-ray Crystallography

Close Packing Activity

Introduction to Miller Indices

Implementation Notes:

This learning object was created at the 2017 IONiC Workshop on VIPEr and Literature Discussion. It has not yet been used in class.

Time Required:

50 minutes

Web Resources:

J. Am. Chem. Soc. 2016, 138, 471-474

10 Apr 2017

Redox Chemistry and Modern Battery Technology

Submitted by Zachary Tonzetich, University of Texas at San Antonio

Evaluation Methods:

I do not grade this activity, but if I did, I would look for class participation in the discussion or assign several of the questions to be turned in at a later date.

Evaluation Results:

My impression of this activity is that it really helps students see the value of redox chemistry. In my experience, the aspects of redox chemistry we teach students (balancing equations, calculating cell potentials, etc.) seem both difficult and esoteric. This activity reinforces these concepts while demonstrating their importance to modern life. One of the biggest realizations the students come to is the relationship between cell voltage and the mass of the materials involved in the redox reaction.

Description:

This In-Class Activity is a series of instructor-guided discussion questions that explore lithium-ion batteries through the lens of simple redox chemistry. I use this exercise as a review activity in my Descriptive Inorganic Chemistry course to help prepare for examinations. However, my primary purpose with this exercise is to impress upon students how basic concepts in redox chemistry and solid-state structure are directly relevant to technologies they use everyday. I do not focus too heavily on the design or operation of the batteries themselves, as other exercises published on VIPEr already do a very good job of that. My intention is to demonstrate how a basic knowledge of redox chemistry is the first step in understanding seemingly complex technologies.

Learning Goals:

The primary goal of this In-Class Activity is for students to solidify their understanding of redox reactions, cell voltages and the relationship between electrical energy and potential. The exercise is also designed to show students how these considerations are part of the design of modern batteries. A secondary aspect of the activity explores the solid-state structure of metal-oxides and how these materials are important to the operation of the battery. At the conclusion of the activity, the student should be familiar enough with calculaing cell voltages and free energy changes that they can critically evaluate the components of a standard battery.

Equipment needs:

None.

Subdiscipline:

Course Level:

Prerequisites:

Corequisites:

Topics Covered:

Electron transfer

Putting electrochemistry to use: Design of new lithium-ion battery anodes

Related activities:

Battery in class activity

Energy Nuggets: Engineering Viruses to Build a Better Battery

Implementation Notes:

I display the pdf file on screen and use the white board to work out simple arithmetic aspects of the exercise, while soliciting responses from the class.

Time Required:

45 minutes

27 Mar 2017

Nanomaterials for Carbon Dioxide Reduction

Submitted by Anne Bentley, Lewis & Clark College

Evaluation Methods:

The problems presented here represented half the points on the final exam – I have included point totals to give an idea of the weight assigned to each problem.

Evaluation Results:

Twelve students were enrolled in my course in the fall 2016. The average overall score for these problems was 78%.

For problem 1b, I calculated the oxidation numbers using the familiar general chemistry method of assigning oxygen as –2 and hydrogen as +1. Students recently coming through organic may have some other way to do it, and you may need to provide directions for your students about your preferred method. I think I could have worded part (c) better to try to emphasize the redox processes involved. I wanted them to think of combustion, but I think they needed to be specifically prompted, such as "Give an example of the combustion processes that generate CO2 and trace the oxidation state of carbon through the reaction." Overall my students scored 86% on problem 1.

The second problem (about another method that could be used to measure d-spacing) was fairly hit or miss. Five students got full credit, six students got 3 points, and one got zero. Eleven out of twelve did answer part (a) correctly. I realized as I made this LO that the article says the carbon-based material doesn’t diffract X-rays, but doesn’t actually directly explain whether or not the Cu nanoparticles diffracted X-rays, so you may need to adjust the question to be technically accurate.

Question three (re: surfactants in nanoparticle synthesis) referred back to knowledge from earlier in the course. The overall score was 61%.

Question 4 (define and describe electrodes) was fairly straightforward, and students scored 85%.

Question 5 caused some confusion, as some students missed that I was looking for “carbon-containing” products only. I didn’t count off for that mistake, but it made the problem harder for students who included hydrogen in each box. Overall, students did very well on this problem (89% correct).

Question 6 – again, not too much trouble here (84% correct).

Question 7 – I was surprised that students didn’t do better on this question, as I thought that water reduction was mentioned often in the article. Only three (of 12) students scored 5 points on this problem, and the average score was 53%. This was probably my favorite question, as it foreshadows electrochemistry topics I cover in my inorganic course.

Description:

This literature discussion is based on an article describing the use of copper nanoparticles on an N-doped textured graphene material to carry out the highly selective reduction of CO₂ to ethanol (Yang Song et al., “High-Selectivity Electrochemical Conversion of CO₂ to Ethanol using a Copper Nanoparticle / N-Doped Graphene Electrode” ChemistrySelect 2016, 1, 6055-6061. DOI: 10.1002/slct.201601169). The article provides a good introduction to the concepts of electrochemical reduction, selectivity and recycling of fossil fuels. The literature discussion assignment shared here was used as half of the final exam in a half-credit nanomaterials chemistry course, but could be adapted for use as a take-home or in-class assignment.

Topics Covered:

Chemical literature

Electron transfer

Corequisites:

Prerequisites:

Course Level:

Learning Goals:

After reading this paper and working through the problems, a student will be able to:

assign oxidation states to carbon and trace the oxidation and reduction of carbon through fossil fuel combustion and CO₂ conversion
describe the role of control experiments in studying the CO₂ conversion presented in the article
define the word “selective” in the context of this research
use the proposed mechanism to explain why the electrode studied produces ethanol in such a high proportion
identify the primary reaction competing with CO₂ reduction for available electrons

Subdiscipline:

Nanochemistry

Kinetics of electrocatalytic reduction of carbon dioxide by Mn catalysts containing bulky bipyridine ligands

Related activities:

Recyclable Catalyst for Conversion of Carbon Dioxide into Formate Attributable to an Oxyanion on the Catalyst Ligand

Dissecting Catalysts for Artificial Photosynthesis

Implementation Notes:

These questions comprised half of the final exam for my half-credit nanomaterials chemistry course in the fall of 2016. I gave the article to the students one week ahead of time. They were encouraged to read the article, make any small notes they liked, and meet with me in office hours with questions. At the final exam they were allowed to use their copy of the article, but they were also required to hand in their copy with their exam so that I could make sure they hadn't written lots of extraneous information on the exam copy.

The nanomaterials course features near-weekly homework assignments centered around articles from the literature. Because I used this article at the end of the course, students were already familiar with nanomaterials synthesis and characterization techniques. Thus, some of the questions I asked relied on previous knowledge.

Please feel free to adapt these questions and add some of your own. Leave comments describing any new questions you’ve added.

Time Required:

one hour

Web Resources:

Link to article

3 Mar 2017

In-class peer review

Submitted by S. Chantal E. Stieber, Cal Poly Pomona

Evaluation Methods:

Student participation was evaluated during the in-class portion based on the questions students asked.

The formal peer review homework was evaluated based on completion, level of thought and thoroughness.

Evaluation Results:

Overall, students were very interested in this topic and had not formally learned about the process before. There was a very lively discussion and a lot of questions were asked. All students received full credit for participation.

Similarly, once students received their classmate's paper for peer review, they took the process very seriously and carefully went through the paper and answered the worksheet questions.

I was very impressed by the high quality of the formal peer reviews that were turned in as homework. Students clearly spent a lot of time to carefully think about the paper and craft a reasonable response. Most students received full-credit.

Description:

This activity includes questions for students to answer to help guide them through the process of peer review. It was designed to assist students in writing peer reviews for research reports written by their classmates, but could be applied to literature articles as well.

Topics Covered:

Chemical literature

Communication skills

Professional skills development

Corequisites:

Prerequisites:

No Prerequisites

Subdiscipline:

Bioinorganic Chemistry

f-block Chemistry

Science Skills, Practices, and Resources

Organometallic Chemistry

Course Level:

Second year

Peer Review - How does it work?: A literature discussion with a focus on scientific communication

Learning Goals:

A student will be able to:

-Explain how the peer-review process works

-Critically read through a research article

-Carefully review a research article

-Write a professional peer review

Related activities:

Implementation Notes:

An overview of peer review was given with three powerpoint slides. Students then worked through a modified Q&A of the peer review module "Peer Review - How does it work?" posted by Michael Norris on VIPEr. This provided students with an example of real reviews, along with the resulting article revisions.

The current worksheet was then passed out to students along with a research report written by one of their classmates (I assigned these and removed names). In class, students answered the questions on the worksheet and were able to ask questions of the editor (the instructor in this case). Following the in-class peer review, students had to write a formal peer review, which was turned in as homework.

The peer review was a final component of a research report that students had been working on throughout the course. The final report was turned in after students had received the review comments back from their peers. The grade of the final report took into consideration whether or not students had made modifications based on comments by their peer reviewer.

Time Required:

60 min

Web Resources:

Peer review policies for Nature

A quick guide to writing a solid peer review

4 Jan 2017

Inorganic Chemistry for Geochemistry and Environmental Sciences Fundamentals and Applications by George W. Luther III

Submitted by Rachel Narehood Austin, Barnard College, Columbia University

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:

Organic Chemistry

Corequisites:

Organic Chemistry

Physical Chemistry: Thermodynamics

Course Level:

Subdiscipline:

Bioinorganic Chemistry

Web Resources:

Companion web site

15 Dec 2016

X-ray Crystallography

Submitted by David Harding, Walailak University

Description:

The website shared here includes excellent simulations concerning a wide variety of techniques commonly used in materials science and inorganic chemistry. I have found it particularly useful for X-ray crystallography as the simulations help understand the lectures.

Course Level:

Subdiscipline:

Topics Covered:

Diffraction

Prerequisites:

Corequisites:

Web Resources:

X-ray Crystallography

28 Jun 2016

Close Packing Activity

Submitted by George Lisensky, Beloit College

Evaluation Methods:

This has been used by the author to illustrate features of class packing in lecture.

Description:

Many extended structures can be viewed as close-packed layers of large anions, with the smaller cations fitting in between the anions. Larger holes between close-packed anions can hold cations with octahedral coordination. Smaller holes between close-packed anions can hold cations with tetrahedral coordination. The online jsmol resources show these layers and their holes.

Learning Goals:

Students will understand octahedral and tetrahedral holes between close packing layers (either hcp or ccp)

Equipment needs:

A physical model kit such as the ICE Solid State Model Kit (see the related activities) could be used. With the linked web resources for this activity students can display individual layers and the holes between them. Both physical and virtual models are valuable learning tools. Either could be used separately depending on availability but they work together well.

Corequisites:

Prerequisites:

No Prerequisites

Subdiscipline:

Introductory Chemistry

Topics Covered:

Extended structure

Course Level:

First year

Hands-On Experience with Close Packing

Related activities:

Solid State Structures

Metal and Ionic Lattices Guided Inquiry Worksheet

Implementation Notes:

For cubic close packing

Click on item 1 and click on Spacefill. Click on item 2 and item 4. What is the arrangement of atoms around each other in Pa, Pb, and Pc layers?

Click on item 1, then item 3, then item 5 to stack layers. The image can be rotated by dragging. You can add or subtract layers by backing up a step or going forward. You can switch between Ball, Spacefill, and Translucent representations.

To repeat the sequence, where should the next layer go? Click on step 6.

Step 7 shows that these layers contain a face-centered cube, stacked along its body diagonal.

Similarly you can experiment by filling in the spaces between the layers. Where can you fit tetrahedra between the packing spheres? Where can you fit octahedra between the packing spheres?

Try switching the display to Ball and Stick with Translucent Polyhedra.

A similar procedure can be used to examine hexagonal close packing.

A note about color: steps with color names in them change the color. Other steps do not. For example if you want the layers different colors use step 1, 2, 4, 7; if you want the layers the same color use steps 1, 3, 5, 6.

Time Required:

30 minutes

Web Resources:

Hexagonal Close Packing

Cubic Close Packing

27 Jun 2016

Online Homework for a Foundations of Inorganic Chemistry Course

Submitted by Sabrina G. Sobel, Hofstra University

Evaluation Methods:

Students are graded on a sliding scale based on the number of attempts on each question. An overall grade is assigned at the end of the semester, adjusted to the number of points allotted for the homework in the syllabus.

Evaluation Results:

Student performance on the overall homework assignments for the semester includes questions assigned on General Chemistry topics that are part of this class syllabus.

	2014	2015	2016
Number	40	47	41
Average	89%	80%	83%
S.D.	15%	19%	23%

In addition to gethering data on overall performance, I and my student assistants, Loren Wolfin and Marissa Strumolo, have completed a statistical study to assess performance on individual questions, and to identify problem questions that need to be edited. We identified two separate issues: incorrect/poorly worded questions, and assignment of level of difficulty. Five problematic questions were identified and edited. The level of difficulty was reassigned for eight questions rated as medium (level 2); six were reassigned as difficult (level 3), and two were reassigned as easy (level 1). I look forward to assessing student performance in Spring 2017 in light of these improvements. Please feel free to implement this Sapling homework in your class, and help in the improvement/evolution of this database.

Description:

The Committee on Professional Training (CPT) has restructured accreditation of Chemistry-related degrees, removing the old model of one year each of General, Analytical, Organic, and Physical Chemistry plus other relevant advanced classes as designed by the individual department. The new model (2008) requires one semester each in the five Foundation areas: Analytical, Inorganic, Organic, Biochemistry and Physical Chemistry, leaving General Chemistry as an option, with the development of advanced classes up to the individual departments. This has caused an upheaval in the treatment of Inorganic Chemistry, elevating it to be on equal footing with the other, more ‘traditional’ subdisciplines which has meant the decoupling of General Chemistry from introduction to Inorganic Chemistry. No commercial online homework system includes sets for either Foundations or Advanced Inorganic Chemistry topics. Sapling online homework (www.saplinglearning.com) has been open to professor authors of homework problems; they have a limited database of advanced inorganic chemistry problems produced by a generous and industrious faculty person. I have developed a homework set for a semester-long freshman/sophomore level Inorganic Chemistry course aligned to the textbook Descriptive Inorganic Chemistry by Rayner-Canham and Overton (ISBN 1-4641-2560-0, www.whfreeman.com/descriptive6e ), and have test run it three times. Question development, analysis of student performance and troubleshooting in addition to topic choices, are critical to this process, especially in light of new information about what topics are taught in such a course (Great Expectations: Using an Analysis of Current Practices To Propose a Framework for the Undergraduate Inorganic Curriculum: http://pubs.acs.org/doi/full/10.1021/acs.inorgchem.5b01320 ).This is an ongoing process, and I am working to improve the database all the time.

Topics Covered:

Acid-base chemistry

Bonding models: Discrete molecules

Descriptive chemistry

Synthesis and reactivity

Prerequisites:

Subdiscipline:

f-block Chemistry

Introductory Chemistry

Corequisites: