Symmetry

10 Jun 2020

A copper "Click" catalyst for the synthesis of 1,2,3-triazoles

Submitted by Chip Nataro, Lafayette College
Evaluation Methods: 

I have not used this in class yet, but anticipate updating this after the fall 2020 semester. This comes as a result of the June 9th LO party.

Description: 

This paper (Gayen, F.R.; Ali, A.A.; Bora, D.; Roy, S.; Saha, S.; Saikia, L.; Goswamee, R.L. and Saha, B. Dalton Trans2020, 49, 6578) describes the synthesis, characterization and catalytic activity of a copper complex with a ferrocene-containing Schiff base ligand. The article is relatively short but packed with information. However, many of the details that are assumed knowledge in the article make for wonderful questions some of which I hope I have captured. The LO includes electron counting using the CBC method, d-orbital splitting, Latimer diagrams and interpretation of catalytic results. There are also opportunities to discuss green chemical practices.

Corequisites: 
Prerequisites: 
Course Level: 
Learning Goals: 

A student should be able

determine the electro count and metal valence in the catalyst

use group theory to determine the number of IR active vibrations in the catalyst

discuss green chemical principles in relation to this article

interpret data from tables and draw conclusions from that data

suggest an additional catalytic experiment that could be performed

Implementation Notes: 

I like the question invoking a Latimer Diagram to get students to rationalize why the copper(I) active catalyst was not isolated. I also enjoyed sneaking in a group theory question. But my favorite quesiton is the last one in which students are asked to go beyond what it presented in the paper and suggest another catalytic reaction to perform. There are some aspects of the paper that were not covered in-depth. In particular the XPS seemed to be a rabbit hole I opted not to go down. The authors do not go into great detail on this topic and perhaps there is a question that could be included, but I opted not to. I also opted not to include anything about the bonding in ferrocene which can be found in many of my other LOs. Also on this list one might include UV-Vis spectroscopy and the computational studies.

Time Required: 
50 minutes
15 May 2020

Inorganic Active Learning Lesson Plan Design

Submitted by Meghan Porter, Indiana University
Evaluation Methods: 

I use the rubric provided, combined with the peer review feedback (due to COVID, they did not have the chance to revise after the peer review process).  Students must also upload a key with their activity which allows me to catch any misconceptions or inaccuracies in their understanding of the material.

I assigned points as following:

Assignment/Key: See above rubric

Reflection: Worth 5 points total- while mostly graded on completion, I did want to be sure my students were providing more useful feedback than 1 word answers so I gave them the rubric below. (pretty much everyone got a 5)

Completed Reflection

5

3

1

What did you learn from completing this assignment? (i.e. What do you feel that you gained from completing it?)

What did you learn from completing other students' assignments?

What are your thoughts for improving the active learning lesson plan assignment in future iterations?  You may answer this referring to your specific lesson plan or this actual assignment of creating a lesson plan.

 

Meets all criteria at a high level, all questions are thoughtfully addressed

Meets some criteria, some questions are not addressed or non-thoughtful response provided

Meets few criteria, most questions not addressed or responses do not demonstrate thought

Peer Review: Spring 2020 was my first time doing the peer review, and of course covid definitely changed the way I had planned on completing it.  My plan was to have them exchange activities in class or in recitation, work through them in small groups, then be able to provide feedback.  Instead, they had to complete it online and provide feedback- I gave them the basic rubic, but changed the scores to categories of "exceeds expectations", "meets expectations", and "does not meet expectations".

Evaluation Results: 

I am always blown away by the creativity of my students!  While some students submit more group worksheet activities, I have had plenty come up with games, relays, building/using playdough, etc...

Students usually report that they thought they knew a topic- only to begin making an activity and realize they didn't understand it as well as they thought they did.  However, by the time the submitted their activity, they felt like they gained a much more in-depth understanding.  They also loved getting to complete other students' assignments this semester.  Their feedback indicated that they felt it was a great way to review, but also get some insight into how their peers think differently about topics.

Side note: Personally, I love seeing how many students tell me afterward that they have a newfound respect for professors after trying to make their own activity! :-)

Description: 

I created this activity as a way to get the class involved in creating new, fun ways to teach course concepts (selfishly- that part is for me) and for students to review concepts prior to the final exam (for them).  Students use a template to create a 15-20 min activity that can be used in groups during class to teach a concept we have learned during the semester.  We then randomly assign the activities and students work in groups to complete them and provide feedback.

The benefits are twofold:

1. My class is about 100-150 students per semester.  This means that each semester I have a large number of new activities (that I didn't have to make!) to use as a starting point in future semesters as I work to create a more active classroom.

2. The students get a review of the topic they have chosen for their activity, plus, they get to review additional topics from completing and providing feedback on two activities from their peers.

I have run this assignment for three semesters now.  It has been a favorite of my students since the beginning!  I have received a number of activities that I now use in class to teach topics!

Learning Goals: 

A student should be able to

  • Create a lesson plan on an inorganic topic that incorporates active learning
  • Demonstrate understanding of chosen topic via an accurate lesson plan key
  • Review multiple inorganic topics through completion of lesson plans from classmates
  • Provide constructive feedback on classmates’ completed lesson plans

 

Equipment needs: 

None

Corequisites: 
Prerequisites: 
Implementation Notes: 

Since this can be used for any level or any topic, there are plenty of variations you can try!  Some things to consider:

1. You can allow students to select any topic from the entire semester for their activity- this can be helpful prior to a final exam when you want a comprehensive review.  You can also restrict topics if you have areas that you feel your students need to focus on or if you want to assign this before a specific exam.  One of my students also suggested having a sign up sheet for topics on a first-come, first-served basis so that you don't end up with 20 balancing redox reactions and zero crystal field splitting.

2. I have tried students designing plans individually and also working in partners to create acitivties (both outside of class).  Both methods worked well, but in a class of 150, that many individual submissions to grade was a bit overwhelming!

3. The peer review was new this semester (based on a previous student suggestion).  My original plan was have them use a recitation section to work in groups through randomly assgined activities.  Due to COVID, they completed the activites on their own- they enjoyed it, but the group experience would ave been more fun.

4. Depending on your timing, you could have them go through the peer review process and then give them a chance to revise the activity based on the feedback prior to you grading it.

5. The student reflection questions are given as a survey on Canvas after they have completed both the lesson plan and the peer review process.

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: 

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