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Capturing the Beauty of Chemistry with an iPad

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In my IB Chemistry class, my seniors were finishing up independent investigations for their Internal Assessment a few weeks ago when something cool happened. One of my students was using silver nitrate and potassium chromate for a titration. This is notable to the story here because the endpoint is marked by the formation of silver chromate as a precipitate, with a deep reddish color. I overhead the student showing his reaction to another student, with both of them commenting on the cool colors involved.

For some reason it got me thinking about one of my favorite reactions: potassium iodide with lead II nitrate. It's a simple double replacement reaction, forming lead II iodide precipitate, which has a vivid yellow color. I've always enjoyed combining two clear, colorless solutions and producing this solid yellow precipitate as a simple demonstration.

 

I mentioned this reaction to the student, and he couldn't remember if I'd shown the class the demo or not. To be fair, it would have been at least a year ago, buried within reactions and the rest of Topic 1: Stoichiometric Relationships. So the student and I set about to film the reaction just to take a closer look. Here's some video of our attempts at filming:

 

 

I'm sure you can find better videos online with high speed cameras looking at the reaction in slow motion. This was just filmed in the classroom - on an iPad - without much thought to background beyond using whiteboards. As you can see from the video, we played around a bit with the best way to film the reaction. Using a dropper ended up being our favorite, and raising the height of the dropper created some really cool effects as well.

 

 

 

 

I've often wanted to create videos of some of my favorite reactions so I could create a library of reactions to share with students. And for some reason, this conversation with my student sparked that curiosity in both of us to look at ways to capture the beauty of this reaction. I think I'd like to capture the single replacement reaction between zinc and copper sulfate next.

 

Do you have any videos of reactions you'd like to share? What is your favorite reaction to demo? I'd love more ideas for the next time a student is interested in filming a reaction.

 

 


Too Many Questions!?!

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Questions?

As we pilot new laboratory activities in the classroom, my students and I are in constant dialogue. Not only do they leave feedback at the end of each lesson (what did you learn, what was your favorite part, what was you least favorite part), but we talk throughout the experiment. Recently our discussion was focused on the questions. As these are guided inquiry activities, they are designed to gently lead students. However, some of my students think some of the questions are very repetitive. As we were talking about the questions together, one student had excellent insight, “I can see how these questions might seem too repetitive for you, but for me, they are teaching me what I need to learn.” This student recognized that in order for her to come to a certain realization she would need to walk through each question step by step.

This is a challenge as an author. How do we design the questions in such a way that there is enough scaffolding for the students that need it, but not so much that others get bogged down in it? By now some of my students have realized that sometimes they will think the questions are too repetitive and are willing to breeze through them instead of getting frustrated. Meanwhile, the rest of the class works through them and then has a light bulb moment. Watching their eyes glow when they make connections is a beautiful sight to behold. What about you? Do you have similar experiences in your classroom?

Bioenergy Institute For Educators

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The Great Lakes Bioenergy Research Center (GLBRC) is pleased to announce the 2016 Bioenergy Institute for Educators to be held June 20-24 at UW-Madison. Bioenergy is an exciting area of research and development and can provide excellent opportunities for engaging students while teaching core concepts in biology, biotechnology, chemistry, environmental science, and agriculture. Join us for an intensive 5-day program to learn about the latest developments in bioenergy research and high-quality, NGSS-aligned materials to use with students. Each participant receives a $500 stipend and classroom materials. Graduate credit available. Accepting applications on rolling basis through May 1, 2016. 

Please visit the program website for more details and application instructions: https://www.glbrc.org/education/educational-programs/bioenergy-institute. Watch 2-min video of highlights from 2015 Institute: https://www.youtube.com/watch?v=4LqdjY1dD8k 

Location: Wisconsin Energy Institute, UW-Madison 

Dates: June 20-24

Questions? Contact Leith Nye, lnye@glbrc.wisc.edu, (608) 263-0809

Time: 
Monday, June 20, 2016 - 09:23 to Friday, June 24, 2016 - 09:23

Research Experience for Teachers in Bioenergy, Sustainable Energy Systems (UW-Madison)

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The Great Lakes Bioenergy Research Center (GLBRC) is now accepting applications for our 2016 Research Experience for Teachers (RET) program, June 20 - August 5. RET participants spend seven weeks conducting research in GLBRC labs and develop related education materials to bring back to their classrooms. Included is a $7000 stipend. We are recruiting four teachers to work on the following projects at UW-Madison:

Yeast Biodiversity, Ecology and Biotechnology
Ecosystem Carbon Cycling in Bioenergy Cropping Systems
Breeding Switchgrass as a Sustainable Biofuel Crop 

Visit our RET program page for full descriptions of the 2016 projects and application information.

To apply: Complete the online application by March 18, 2016. 

Questions? Contact Leith Nye, lnye@glbrc.wisc.edu, 608-263-0809

Time: 
Monday, June 20, 2016 - 09:31 to Friday, August 5, 2016 - 09:31
Event Type: 

Quick and Easy Lab Practicals...

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What am I doing to help kids achieve?

How do I know when they are there?

What is the evidence?

Flinn Scientific has a great elearning video series. Many of the videos have master teachers demonstrating some great labs and techniques that they do in the classroom. A general theme in many of the videos seems to be combining demonstrations, labs, calculations and lab practicals. The nice part about what occurs is that for whatever concept the students are doing, it is not enough to come up with an answer on paper. They have to use that answer for a prediction and then see if they are correct actually checking and manipulating material. This idea has added a new dimension to my classroom. Students who are tired of "pen and paper" work now get to get up and use their answers to mass something or find the volume of something and see if they are correct. I have tried to add more of these to my lessons.

  This week I did "The Murky Myster of Matter Measurement" by Chad Bridle. Basically, students are working at making a series of predictions and measurements concerning the mass, volume and ultimately density of two different types of beads. It can be found at the Grand Valley State site. It was the first time I used this activity and I will certainly use it again. It encouraged kids to solve problems multiple ways. It brought in other math concepts. It was an easy set up that can be repeated from year to year. It was well received by students and they experienced success. After it was over, I put away all of the balanced except for one that I had. I challenged some students to see if I gave them a certain volume, could they predict exactly what the balance would say before they placed the beads on the balance? They had still had to do the "pen and paper" but asking them to then physically check it and get instant feedback added a new dimension that was helpful for them and exciting for me to see as a teacher.

  The next lab we are doing is a traditional "mole" lab in which that I got from Zumdahl "World of Chemistry". Students get 4 types of dry beans. They count out 50 of each and get the mass, the relative weights and how many are in a "pot". A "pot" is defined as the number of beans that it would take to get the relative weight of that bean. Students are guided to the idea that the relative weights, the "pot" and the number of beans in a pot is similar to the atomic masses of the elements, moles and Avogadros number. After they finish the lab I am thinking of the added challenge of a problem in which they are provided a certain number of "pots" of a bean or number of beans, they have to predict the mass and then put that many on the scale that I have. Kind of like a min lab practical. They have to hand me their work, the beans and they will be placed on the scale and they will get instant feedback...did they get it correct or not???

   Do you do a cool lab practical with instant feedback??  If so..I would love to hear from you...

 

"Even Einstein Struggled: Effects of Learning about Great Scientists’ Struggles on High School Students’ Motivation to Learn Science"

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           What motivates our students to excel in understanding chemistry? For some students, they would like to pursue a career in a science related field while others are extrinsically motivated for a particular grade or graduation credit. Despite each student’s intention for learning, one aspect that many educators may overlook are the perceptions of how scientific breakthroughs were discovered. Many consider Albert Einstein, Marie Curie, and Michael Faraday elite minds and assume their work was a gradual process, without challenges or setbacks. In contrast these visionaries not only struggled professionally in their respective field of study, they had to overcome struggles in their personal lives as well.

            “Even Einstein Struggled: Effects of Learning About Great Scientists’ Struggles on High School Students’ Motivation to Learn Science” is a study published in the Journal of Educational Psychology this month which proposes that students should learn about the struggles of Einstein, Curie, and Faraday as well as how their work pertains to the curriculum. “Because overcoming failure is a natural part of science learning, the current study attempted to present students a realistic picture of doing science by emphasizing failure and the amount of effort required to succeed in science” (Lin-Siegler, p.10).  When students were provided with either scientists’ life stories or their experimental struggles, in addition to the curriculum, their scientific learning improved. Conversely, when students were only presented with the accomplishments of the previously mentioned scientists, their scientific learning stayed consistent with previous data collected or potentially decreased.

            Although educators may debate the necessity of including the personal and professional struggles of scientists into their chemistry curriculum, what should be considered is the connection that could be made with any student, especially those who have a low interest and/or ability in chemistry. Achievements in chemistry should not be perceived as an unattainable goal for students. Instead these achievements should be a result of continuous effort both academically as well as personally.

            If any educator has spent instructional time on providing their students with academic and life struggles of various scientists, I would love to hear from you. Feel free to leave your comments below as well as any suggestions in regards to how to incorporate these ideas into chemistry curriculum.

 

Pick Attribution: 

Journal of Educational Psychology 

American Psychological Association 

Publication Date: 
Thursday, February 11, 2016

Using Chemistry to Find that Silver Lining

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Silver plate: before and after

I recently gave a public lecture on my campus in which (among other things) I discussed the chemistry of metallic copper, silver, and gold. During the talk I conducted a chemistry demonstration very similar to the Journal of Chemical Education’s Classroom Activity #25: Silver to Black – and Back.1 Through the process of conducting this experiment several times, I learned quite a bit about the chemistry of silver. The things I learned touch on several topics in chemistry that might be of interest to your students. If you’d like to skip my musings on this subject and simply watch videos of the demonstration, scroll down to the videos at the bottom of this post.

The main focus of JCE Classroom Activity #25 is the demonstration of the formation and removal of tarnish from items made of silver. Silver tarnish results from the formation of silver sulfide from the reaction between silver, oxygen, and hydrogen sulfide:2,3

2 Ag(s) + ½ O2(g) + H2S(g) --> Ag2S(s) + H2O(l).

Hydrogen sulfide is released into the atmosphere from sewers, factories, and farms. Hydrogen sulfide can also form from the reaction between carbonyl sulfide and water:

OCS(g) + H2O(l) --> H2S(g) + CO2(g)

Carbonyl sulfide is expelled into the atmosphere from volcanoes and the ocean. Both hydrogen sulfide and carbonyl sulfide are considered to be particularly effective in forming tarnish on silver.2,3

Fortunately, it is relatively easy to remove tarnish from silver, because several metals are more reactive than silver. It is easy to see the metals that are reactive than silver by inspecting the metal activity series (Figure 1). Any metal higher than silver on the series is more reactive, is more easily oxidized, and is more likely to react with sulfide ions than silver.  

Figure 1:Metal activity series. Because magnesium and aluminum are higher in the series than silver, both of these metals are more likely to bind with sulfide ions than silver.

Thus, by treating tarnished silver with aluminum foil, the chemical transfer of sulfide ions from the tarnished silver to the aluminum foil takes place:

3 Ag2S(s) + 2 Al(s) --> Al2S3(s) + 6 Ag(s)

Because I wanted to see this reaction take place for myself, I bought several tarnished silver items on eBay.4 As I experimented with the removal of tarnish using aluminum, I noted that some tarnish was particularly resistant to removal with aluminum. Seeing that magnesium is higher than aluminum on the activity series, I decided to try to use magnesium as a tarnish remover:

 Ag2S(s) + Mg(s) --> MgS(s) + 2 Ag(s)

Sure enough, because magnesium is more easily oxidized than aluminum, I found it to be particularly good at removing the tarnish from silver. I’m not the first one to have this idea. Apparently a product called “Maggie Pan”, which is no longer sold, used magnesium as a silver cleaner.5 

This experiment – the removal of tarnish with aluminum foil or magnesium – is quite easy to accomplish. While it does take a bit of time, the results are impressive and I think your students will enjoy seeing the process take place. Check it out in the video below:

Once you have chemically removed the tarnish from your silver item, you might want to conduct this experiment again for another group of students. However, the formation of tarnish on silver from gases in the atmosphere usually takes several years. In JCE Classroom Activity #25, it is suggested that egg yolk, mayonnaise, powdered sulfur, and mustard applied to silver will cause it to tarnish in about 24 hours.  While testing out these suggestions, I quite by accident discovered a way to form tarnish on a silver item in less than one hour.6 You can see this process of discovery unfold in the video below:

I find it interesting to note that in JCE Classroom Activity #25, it is claimed that the yolk of an egg in contact with a silver item will cause the silver to tarnish. Therefore, I was surprised to find that a hot egg white did the trick in less than an hour.7 I wish I had monitored the experiment more closely to try to observe how quickly the tarnish formed. Because I set the experiment aside and didn’t check on it until an hour later, I don’t know how long it took for the hot, hard-boiled egg white to tarnish the silver plate. Did it take less than 30 minutes? What about less than 10 minutes? I don’t know the answer to this question! If you get the chance, maybe you or your students could repeat this experiment and report back how quickly tarnish forms on a silver item through treatment with a hot, hard-boiled egg white.

NOTES:

1. JCE Editorial Staff; JCE Classroom Activity #25: Silver to Black – And Back. J. Chem. Educ.2000, 77, 328A – 329A.  

2. J. Novakovic, J.;  Vassiliou, P.;  Georgiza, E.; Electrochemical Cleaning of Artificially Tarnished Silver. Int. J. Electrochem. Sci., 2013, 8, 7223 – 7232.

3. Salas, B. V.; Wiener, M. S.; Badilla, G. L.; Beltran, M. C.; Stoycheva, R. Z. M.; Diaz, J. D. O.; Osuna, L. V.; Gaynor, J. T.; H2S Pollution and Its Effect on Corrosion of Electronic Components.  

4. Surprisingly, I purchased all silver items for less than $10 each. It appears that people are quite willing to sell tarnished silver items for substantially less than untarnished silver.

5. Google “Maggie Pan silver cleaner” and you might find this vintage product on sale on Ebay or elsewhere online!

6. Do not attempt to add tarnish to your fine silver for these experiments. In some experiments I conducted I was not able to remove purposely added tarnish – even when using magnesium. This mostly occured when I used powdered sulfur to tarnish the silver items.

7. It makes sense to me that the egg white would form tarnish. Egg white is primarily made of protein, and the sulfur containing amino acids cysteine and methionine are found ubiquitously in proteins. 

BCCE 2016

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Early Registration for BCCE now open!

BCCE 2016 will be held at the University of Northern Colorado in Greeley, CO.

July 31 – August 4, 2016

BCCE is not just for higher education anymore! Twenty years ago, a new high school teacher would often be told that ChemEd was the conference for them to attend (and it is certainly recommended!). It is only a biennial event and BCCE happened on the other years. Then, those experienced teachers would tell the newbie that BCCE was intended for higher ed. Well, there will be plenty of high education folks in attendance, but if you are a high school teacher, you will not be alone! High school teachers do fit in and you will find more than enough to do to fill your time and give you plenty of value for the price of the trip. High school teachers can register for the discounted rate of $186 through June 1st. On campus housing is available aside from several local hotels. Be sure to check out the many extra events that can be enjoyed before, during and after the conference to take full advantage of the adventourous location.

 

Time: 
Sunday, July 31, 2016 - 14:48 to Thursday, August 4, 2016 - 14:48
Event Type: 

What is it a student should be able to do and explain? How do we find that out???

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mole activity

What am I doing to help kids achieve?

How do I know when they are there?

What is the evidence?

  A perfect storm starts to form. We are on the concept of moles and I have some students who are struggling mathematically. It is a rough time of year to get kids excited. Many students are struggling with ACT and SAT prep and as a teacher, I am tired of test...test...test. Also, I had about two dozen 2 liter bottle "pre forms" that I needed to find something to do with.

  I made up four sets of bottles, each containing different amounts of elements in each one, one type of element per bottle. Should a student select a bottle from the first two sets (numbers 1-12), they must get the mass, subtract out the mass of the bottle (which I provide) and calculate either the moles of the element in the bottle or the number of atoms in the bottle. If they get a bottle from one of the second two sets (numbers 13-24) then they are provided either the number of atoms of the element in the bottle or the moles of element and they need to calculate the total mass (including the mass of the bottle which I provide). They then compare their written answer with what they get when they place the bottle on the scale that I control.

All students must perform three tasks. First, they must physically do something besides just write answers on a piece of paper. All students have to collect some data that involves the mass and know what to do with it. Second, they have to be able to communicate their problem solving capabilities on paper. Having an answer, even if it is the correct answer, is not enough. They have to demonstrate a reasonable thought process. Finally, they need to get a correct answer. The closer they get to the correct answer, the better the grade.

  Sure, this took awhile to set up. I have 24 different bottles. There are four sets with 6 different elements in each set and there are no two bottles that are the same overall mass. All data has been entered into a master spreadsheet so when a student provides an answer, I can check, provide immediate feedback within seconds and say, "Nice job" or "Try again". Most students generally make the mistake of forgeting about the mass of the bottle. Copying is virtually impossible. No two bottles are exactly the same. Students have three tries and I grade the best two. Also, they are up and moving around which tends to wake them up. Is this as good as a traditional "test"? That depends on the question..."What is it that we really want a student to be able to do and explain?"

  This is a tough time of year to teach. Here is a thought...try to plan something this week in which your students will see you having fun, something you are passionate about, or both. As for me....I am kind of excited about trying to find a better way to see if students can explain the concept of moles....hopefully it will work.

Group Work Dilemma - What Would You Do?

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What would you do?

Hello Readers!

 

There have been a TON of great ideas for guided inquiry (modeling instruction, POGIL, Target Inquiry, etc.). I do a ton of guided inquiry in my classroom. I have engaged in professional development on facilitating group work (through POGIL) and read what I hear is THE book on group work (which really is quite good- “Designing Groupwork”).

 

Basically, facilitating group work is challenging. These guided inquiry tasks are NOT just worksheets. They are data sets that need to be analyzed and dissected, and meant to be analogous to patterns of thought chemists would do to analyze data (ok, ok lots of it is fabricated, but still, it IS what professional chemists do with their data).

 

In this blog post, I am going to share a VERY sticky situation from my AP Chemistry classroom to you fine teachers. This event happened a few weeks ago and it is still bugging me. At some point in the near future, I will share what I did next as a comment to this blog post (what a cliffhanger!).

 

So, my AP chemistry class looks like this:

  • 20 students (60% male, 40% female)

  • All are in the 10th or 11th grade

  • All took one year of chemistry with me (either general or honors chemistry)

  • Varying math levels (Alg II through beyond Calc I)

  • Students are allowed to choose their own seats

  • We meet for six 55 minute periods a week

    • In addition to one 55 minute period each day, one day a week they stay for a “double period” so we have more time for labs. AP Chemistry is taught the last period of the day to facilitate this practice.

  • Our school is a self proclaimed problem based learning school - students are expected to engage in tasks that make them do the heavy lifting.

 

The Dilemma:

  • Students engage in a variety of tasks in my class: lecture, guided inquiry (both in and out of the laboratory), and sometimes time to work on practice sets.

  • I have one student who I will call Josh (not his real name). Josh has been a pretty high achiever both last year and this year.

  • However, Josh has not demonstrated that he trusts the students in his group. He will try to isolate himself even though he sits between two other students.

  • A few weeks ago, my students were working on a lab titled “Energy in Chemical Reactions” (basically, they were using Q=mcΔT in a variety of scenarios).  

  • The first day of the lab, most students figured out how to successfully apply the use of Q=mcΔT in the lab scenario.

  • On day 2, most students were fine continuing the lab with just a different system, but using the same ideas. While working that day, Josh was seriously confused about how to use Q=mcΔT - he kept wanting to find the change in enthalpy per mole of reaction instead of the total Q. He was frustrated that his calculations didn’t jive with other data students had posted on the board.

  • When he called me over for help, after I asked him what he and his group mates had worked out so far, his response was blatantly said “My group members don’t know so I haven’t asked them.”

  • I told him he needed to engage his group members before I would come over again to actually help. Then I left.

 

My Take:

I felt like if 85% of the class was fine it did not warrant a whole class re-teach and I was not helping Josh by showing him how to do it if he had so many resources at hand.

 

On one hand, I felt like a terrible human being to leave Josh in the lurch. On the other hand, I felt like he was being disrespectful to his peers that had valuable contributions to the conversation at hand that he chose to not engage in. I felt like my choice was better for him in the long run.

 

Welcome to my classroom. It is often challenging. It is at times frustrating. It is always loud. It is where my students learn.

 

What I would like to know in your response below:

  • What other questions might I ask myself about this scenario?

  • What would you have done in my place?

  • What would your next steps be?

  • What struggles do you have with facilitating group work?

 

The Art of the Chemical Demonstration

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demonstrations

One of my favorite things to talk about with my colleagues is the use of lecture demonstrations in teaching. There seems to be a push in my district to stop using chemicals whenever possible and get to computer simulations and video in place of wet chemistry. I don’t think they are thrilled with me since I can’t envision ever taking the chemistry out of chemistry.

I often like to finish off a chapter or unit with an hour long demonstration based review lecture. This allows me to engage the students in a meaningful conversation about the material that they are about to be tested on. Since it is the end of the unit I often ask them to tell me what is going on in a demonstration and how it is relevant to the material we are covering rather than me explaining it. One technique I learned while working at the Institute for Chemical Education at UW-Madison was to have a student pretend to be a radio sportscaster and describe what they are seeing and even have a second student join them to provide some “color” commentary about the demonstration.

Having kids describe demonstrations has shown me how often a student’s mind goes in directions I had never anticipated. This is sometimes a good thing, but mostly bad. So having an opportunity to take a day and make them describe to me on the spot what they “see” in a chemical reaction is an excellent technique to open the lines of communication. I am hoping over a series of several of these posts to describe the demonstrations I am using and what I am trying to get out of them. It has pushed me to have some real soul searching discussions with my fellow chemistry teachers at my school to evaluate why we are doing certain demonstrations, labs, and lessons.

My first thought with these posts is to revisit the six characteristics of an effective demonstration from the Shakhashiri books. They are:

1) Demonstrations must be timely and appropriate.

I have had a colleague that went to every workshop they could find and came back and just did whatever they saw at the workshop the previous weekend. The kids liked the class but when AP Test time came around they were the only teacher on campus to have straight scores of 1. The students learned little abut the material and had no take home understanding of the subject matter.

2) Demonstrations must be well prepared and rehearsed.

If you don’t know how it works and what is going to happen, everyone is in danger. A different colleague of mine once tried doing an iodine clock demonstration where you pour 200 mL of solution A into a large beaker with 200 mL of solution B. The problem was he poured the large beaker into the small beaker. Imagine the mess that he made.

3) Demonstrations must be visible and appropriately scaled.

A different colleague from many years ago used to turn his back to the students and hold beakers in his hand and write equations on the board describing what the students could not see. Not much learning there. Sadly this teacher was also seriously injured years later when performing a demonstration without proper safety protocols.

4) Demonstrations must be simple and uncluttered.

One of the teachers I went through teacher training with refused to decorate his bulletin boards because he said he wanted to be the most interesting thing in the room. Keep the kids attention on himself he said. Well this might be an over statement of the idea but we do need to keep our students focused on what is important about a demonstration.

5) Demonstrations must be direct and lively.

Remember the science teacher from the show “The Wonder Years”? He was played by Ben Stein. He could put a room to sleep faster then a pound of Ambien.

6) Demonstrations must be dramatic and striking.

Just hopefully not striking the kids or instructor.

So keep tuning in for a few more posts about chemical demonstrations.

 

Shakhashiri, Bassam Z. Chemical Demonstrations: A guide book for teachers of chemistry, Volume 1-5, University of Wisconsin Press, 1983-2011

 

JCE 93.03 March 2016 Issue Highlights

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Journal of Chemical Education March 2016 Cover

Chemical Information Special Issue

The March 2016 issue of the Journal of Chemical Education is now available online to subscribers. The entire issue is devoted to topics on various aspects of chemical information and information literacy: chemical education research on information literacy; chemical information literacy for undergraduates; chemical information literacy for graduate students; prototypes and best practices; discovery.

Cover: Chemical Information

How chemical information is produced, distributed, discovered, managed, shared, and preserved has changed significantly in the past two decades—understanding how to navigate this digital landscape is essential for students, educators, and researchers. In response to a call for papers on chemical information, chemistry educators from around the world have contributed papers collected in this special issue on chemical information to share approaches to developing information literacy skills in students. Papers in this issue aim to be a resource for ideas and a catalyst for expanding communication and collaboration between chemists and information professionals. Contributions to the “Journal of Chemical Education Special Issue: Chemical Information” have a designation that they are part of the collection published in this issue. (Cover photo courtesy of Grace Baysinger.)

Editorial

Grace Baysinger serves as the Head Librarian and Bibliographer of the Swain Chemistry and Chemical Engineering Library at Stanford University and was the guest editor for this special issue. In her Editorial, she introduces and contextualizes the Journal of Chemical Education’s “Special Issue: Chemical Information”.

Chemical Education Research on Information Literacy

Exploring the Information Literacy Needs and Values of High School Chemistry Teachers ~ Marci Zane and Valerie Karvey Tucci

Student Development of Information Literacy Skills during Problem-Based Organic Chemistry Laboratory Experiments ~ Ginger V. Shultz and Ye Li

Chemical Information Literacy for Undergraduates

The Stepping Stone Approach to Teaching Chemical Information Skills ~ Andrew A. Yeagley, Sarah E. G. Porter, Melissa C. Rhoten, and Benjamin J. Topham

Chemical Information Literacy at a Liberal Arts College ~ George E. Greco

A Combination Course and Lab-Based Approach To Teaching Research Skills to Undergraduates ~ Amy M. Danowitz, Ronald C. Brown, Clinton D. Jones, Amy Diegelman-Parente, and Christopher E. Taylor

Combining Chemical Information Literacy, Communication Skills, Career Preparation, Ethics, and Peer Review in a Team-Taught Chemistry Course ~ Mary Lou Baker Jones , Paul G. Seybold

Integrating Chemical Information Instruction into the Chemistry Curriculum on Borrowed Time: A Multiyear Case Study of a Capstone Research Report for Organic Chemistry ~ Danielle L. Jacobs, Heather A. Dalal, and Patricia H. Dawson

Integrating Chemical Information Instruction into the Chemistry Curriculum on Borrowed Time: The Multiyear Development and Evolution of a Virtual Instructional Tutorial ~ Danielle L. Jacobs, Heather A. Dalal, and Patricia H. Dawson

Interdisciplinary Explorations: Promoting Critical Thinking via Problem-Based Learning in an Advanced Biochemistry Class ~ Chapel D. Cowden and Manuel F. Santiago

Integration of EndNote Online in Information Literacy Instruction Designed for Small and Large Chemistry Courses ~ Svetla Baykoucheva, Joseph D. Houck, and Natalia White

The Effect of Peer Review on Information Literacy Outcomes in a Chemical Literature Course ~ David A. Zwicky and Michael D. Hands

Chemical Information Literacy for Graduate Students

Replacing the Traditional Graduate Chemistry Literature Seminar with a Chemical Research Literacy Course ~ Vincent F. Scalfani, Patrick A. Frantom, and Stephen A. Woski

Introducing Graduate Students to the Chemical Information Landscape: The Ongoing Evolution of a Graduate-Level Chemical Information Course ~ Judith N. Currano

Progressively Fostering Students’ Chemical Information Skills in a Three-Year Chemical Engineering Program in France ~ Christel Gozzi, Marie-José Arnoux, Jérémy Breuzard, Claire Marchal, Clémence Nikitine, Alice Renaudat, and Fabien Toulgoat

Prototypes and Best Practices

Creating an Adaptive Technology Using a Cheminformatics System To Read Aloud Chemical Compound Names for People with Visual Disabilities ~ Haruo Kamijo, Shingo Morii, Wataru Yamaguchi, Naoki Toyooka, Masahito Tada-Umezaki, and Shigeki Hirobayashi

Big Data and Chemical Education ~ Harry E. Pence and Antony J. Williams

Improving Information Literacy Skills through Learning To Use and Edit Wikipedia: A Chemistry Perspective ~ Martin A. Walker and Ye Li

The Safety “Use Case”: Co-Developing Chemical Information Management and Laboratory Safety Skills ~ Ralph B. Stuart and Leah R. McEwen

Discovery

The Concept of the Imploded Boolean Search: A Case Study with Undergraduate Chemistry Students ~ Robert Tomaszewski

Using Patent Classification To Discover Chemical Information in a Free Patent Database: Challenges and Opportunities ~ Stefan Härtinger and Nigel Clarke

Crystallographic Information Resources ~ Leslie Glasser

Discovering More Chemical Concepts from 3D Chemical Information Searches of Crystal Structure Databases ~ Henry S. Rzepa

Discovering Reliable Sources of Biochemical Thermodynamic Data To Aid Students’ Understanding ~ Eduardo Méndez and María F. Cerdá

Using Citation Indexes, Citation Searching, and Bibliometrics To Improve Chemistry Scholarship, Research, and Administration ~ Robert E. Buntrock

Determining Synthetic Routes to Consumer Product Ingredients through the Use of Electronic Resources ~ Brian E. Love and Lisa J. Bennett

RCSB Protein Data Bank: A Resource for Chemical, Biochemical, and Structural Explorations of Large and Small Biomolecules ~ Christine Zardecki, Shuchismita Dutta, David S. Goodsell, Maria Voigt, and Stephen K. Burley

Mining the Archives:AP Chemistry Special Issue

The first special issue published by the Journal of Chemical Education in September 2014 was on the topic of AP chemistry curriculum and assessment redesign in response to the College Board’s new framework emphasizing big ideas, enduring understandings, and science practices. Chemistry educators at the high school and college levels contributed papers collected in this special issue on AP chemistry to share ideas, best practices, perspectives, and recommendations for action.

Greg Rushton introduced and contextualized the Journal of Chemical Education’s Special Issue: Advanced Placement (AP) Chemistry.

Deanna Cullen listed the 20 commentaries, articles, and labs in the AP Chemistry Special Issue as a Pick on ChemEdX.

Every Issue of JCE Is Special and Full of Information

With 93 volumes of the Journal of Chemical Education to explore, you will always find something informative—including the articles mentioned above, and many more, in the Journal of Chemical Education. Articles that are edited and published online ahead of print (ASAP—As Soon As Publishable) are also available.

If you are considering writing an article for JCE, there are numerous author resources available on JCE’s ACS Web site, including recently updated Author Guidelines, Document Templates, and Reference Guidelines.

Especially JCE: March 2016

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Is the cover of the March 2016 issue (see photo) of the Journal of Chemical Education a familiar scene? It is to me. I’ve spent many hours surrounded by shelves full of books and journals, in all of their papery goodness. Paper was the mainstay of my undergraduate searches in the chemistry library, although computer searches (to lead me to paper) also played a role. Since then, the landscape has changed dramatically, with far-reaching effects on both students and educators.

This month’s special issue puts the focus on that chemical information and information literacy landscape, with “perspectives, practices, and programs of potential use to educators and librarians in higher education and high school,” (p 401) as Grace Baysinger’s editorial (full text freely available) states.

Information Literacy Needs

Exploring the Information Literacy Needs and Values of High School Chemistry Teachers begins with a definition of information literacy (IL), the “set of abilities requiring individuals to recognize when information is needed and have the ability to locate, evaluate and use effectively the needed information” (p 406). Are you “information literate”? Are your students? What role can chemistry educators play in helping their students to become information literate? How can educators be prepared for this role?

Zane and Tucci are interested in the answers to all of these questions. Their article describes the first steps in their quest to improve the IL component of a seminar connected to their college’s chemistry department, based on the needs of high school chemistry teachers. They surveyed members of the American Association of Chemistry Teachers (AACT) and New England Association of Chemistry Teachers (NEACT). The article’s figures summarize teacher responses related to the priority of IL in the chemistry curriculum, the use of specific IL skills in their curriculum, difficulties in implementing IL, and the types of information sources used by their students. From the results, many participants already include components of IL in their chemistry curriculum, although the main difficulty (can you guess?) is lack of time.

The authors conclude that more information is needed, including more input from chemistry teachers, particularly in IL instruction that is already being used. Do you integrate IL into your classroom already? What insights can you offer to others? 

 

Information Literacy Skills: Wikipedia Activity

Survey results from the Zane and Tucci article above show that websites are the top information source used by students in the chemistry curriculum. It’s probably safe to say that Wikipedia pops up as one of those websites from time to time. In Improving Information Literacy Skills through Learning To Use and Edit Wikipedia: A Chemistry Perspective, Walker and Li discuss facets of the resource: its chemistry content, how students can use it effectively, and how it can be a benefit to developing information literacy skills.

I like their recommendations for how Wikipedia can be useful, such as using it as an easy-to-understand first overall read on a topic, “an excellent way for a beginner to quickly see connections and the bigger picture” (p 511) and as a possible resource for identifying key papers for a topic, based on the Wikipedia article citations.

The second half of their article focuses on using Wikipedia as part of an editing project for students. Full involvement in the activity is intensive and is aimed at undergraduate and graduate levels, usually with support from librarians. However, the authors make suggestions for how a project with a smaller scope could also be implemented, which could be of use in the high school classroom. These include adding a small part to an existing article, adding citations, adding images, editing short sections, and correcting mistakes in existing articles. They suggest an instructor first learn about how the Wikipedia editing community works and to experience editing an article themselves.

What has your experience been with students using (or not using?) Wikipedia in the classroom?

For the entire issue, see Mary Saecker’s JCE 93.03—March Issue Highlights.

Share!

What are your thoughts on the March 2016 issue? If you see an article that sparks your interest, please share! You can comment on this post, or if you’d like to contribute an article or “Pick” of your own, submit a request to contribute, explaining you’d like to contribute to the Especially JCE column. Questions? Contact us using the XChange’s contact form.

Game On! IChO is back

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Chemistry Olympiad

Many of you familiar with me will know I have a great affinity for academic competition and was more than a little bit upset when the International Chemistry Olympiad was scheduled for Karachi Pakistan in 2016. As I feared the United States Department of State denied travel documents to anyone who wished to visit Pakistan (I totally agree with their decision) and the team from the United States would not be able to travel to the IChO. This also meant that the national study camp at the Air Force Academy would be cancelled. However I am reminded of a phrase popular from my youth, “Did you ever throw a party and no one came?” Most every country decided not to send teams and the government of Pakistan withdrew their support for the event this last January.

After what I imagine was some very fast planning, the event was relocated to Tbilisi, Georgia. I think (I might be wrong) that this was the country chosen to host the event about 2-3 years down the road. So game on! The United States will be holding a study camp and will be sending a team to Georgia. I assume the study camp will still be held at Air Force but one of my former students who is currently a cadet their tells me their might be a problem.

I am very excited! I truly love academic competitions and have seen how much participating in them has affected my students and myself. It has made me a much better teacher, made my students reach much higher, and provided many opportunities to many kids that they otherwise would have never had. I have had the privilege of having a student be on Team USA in Physics (although he has not chosen to be on the traveling team) and learned from him that just going to the study camp was the most amazing academic experience of his career.

So if you are looking for something to push your teaching to the next level try checking out Chemistry Olympiad.

When am I ever going to use this????

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What am I doing to help kids achieve?

How do I know when they are there?

What is the evidence?

  Fortunately, I am blessed to work with some fantastic people who, after a number of years, understand my nerdiness and have accepted it. A great colleague passed this along. I jumped on it.  If you go to this site on Etsy (Que Intersante. Where Geek Meets Art) you can get a great project for you kids for not too much money.  Essentially what this site sells are Crayon labels. They are not just ANY Crayon labels...they are labels that go on colored Crayons or pencils and, instead of having a name such as "orange", it has the chemical symbol or the compound or element that makes up that color. I got the labels. Next, I went to a local craft store, got a big box of 64 Crayons, some colored markers, a canvas and a hot glue gun. Thanks to coupons in the Sunday paper I did not have to spend more than $20. I had some kids that needed some extra credit. They transferred the labels onto the crayons and markers. They then hot glued the crayons and markers to the canvas (making sure the labels were showing of course). Now, whenever we are talking about transition metals or compounds with transition metals I can show them the board and say, "Here is how we get these colors in nature." Way cool project, cheap and easy.  Also, you wind up with a nice educational tool that you can refer to throughout the year.

Publication Date: 
Sunday, March 13, 2016

Four Ways to Fight Spring Fever

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spring

Today is the first day of daylight savings time. Ouch. My students are sleep-walking, zombie-like creatures with a single obsession: the countdown to Spring Break. Their teacher is no different this morning. Tomorrow, I plan to change my attitude.

How can I engage my students (and myself) for the last half of the semester? I read recently that the human attention span in 2015 is 8.25 seconds, which is down from 2000’s 12-second span. Currently, we are just beneath goldfish, who can attend to one thought for 9 seconds. I’m not sure of the methods of the research study, and I maintain a level of healthy skepticism. However, I admit my thoughts often spring from topic to topic like a bubble gum machine bouncy ball.

I asked a sophomore, Jacob, to give me tips on keeping him focused in class. He replied, “When I’m sitting in class, I pick up my phone and start messing with it. I’m listening, but I need something to do. I really like the flipped classroom. The only time anyone really focuses on working problems is in class with you anyway. Oh, I like all the video clips you use in our lectures, too. The “Crash Course” guy is funny.”

From the mouths of babes, “I need something to do.” Here are my ideas:

1) Demonstrations: We began equilibrium today, and I used a “Blue Bottle” demonstration to introduce the idea of reversible reactions. My students opened their curious eyes for a few moments. Many made predictions on whiteboards. Some asked questions. A few gasped at the color changes.

Here are some links to simple demonstrations that do not require a ton of set up time:

  • University of Washington Department of Chemistry: If you can’t find it here, it doesn’t exist. You’ll find a very long list of lecture demonstrations divided by content. The blue bottle experiment instructions were simpler and smaller scale here than on other more well-known sites.
  • University of Washington Department of Chemistry: This site gives short video clips explaining the chemistry behind the demonstration as well as the demo. The clips are engaging, and they allow me to show phenomena outside of my school budget.
  • Flinn Scientific Demos: Old Faithful. Nearly everyone knows Flinn’s tried and true demonstrations. 

2)Video Clips: As Jacob mentioned, I use lots of video clips during any teacher-centered time. The clips add dynamic visuals, new lab techniques, humor, and simply, a different voice to the lecture time.

Here are some links to clips my students seem to enjoy:

  • ChemEdX has many, many pages of video clips on a really wide range of topics. The clips are short. They offer the perfect punch to reinforce an idea, grab interest, or give a moment of processing time. These do require a paid subscription to ChemEd X.

  • Crash Course Chemistry: Hank Green offers 46 videos on chemistry content. He speaks incredibly fast, but his humor really engages the students. I show the videos as a 10 to 15 minute preview/overview of a new unit. I create viewing guides to help my students keep up with Hank’s pace.
  • Bozeman Science: Similar to Flinn Scientific, Bozeman Science is tried and true. The short clips are complete with graphic organizers and slideshows. I use these in class, and the students use them as review for tests and quizzes.

3)Music: The fastest way to change the atmosphere of the classroom is to play music. Purposeful choices are excellent, but anything will work. Students respond to the style and tempo of the music.

Here are a few of my favorites:

  • Theme days: Motown Monday, Twangy Tuesday, The Middle Wednesday, Throwback Thursday, Free Play Friday – I created short playlists for each day of the week, and I play the songs during class changes. The students come and go to music. It really helps set the tone for a positive class time.
  • Mr. Rosengarten is funny, really funny. He has written and performed many, many chemistry songs and raps complete with music videos. No, he is not a professional rapper. Think of your chemistry teacher. Now imagine him rapping. Here are a few titles to get you interested:  “Rock Me Avogadro” and “For Those about to Dissolve: We Solute You.”
  • Partner Discussion and Problem-Solving Time: During my second year teaching, a staff development meeting hit home to me. I didn’t often speak up about chemistry content in small group discussions for fear of making a mistake and being overheard by other groups. The instructor told us to never ask students to speak about content for the first time without providing background noise. Wow. I follow the advice. My students always have the safety of “noise” during their first formative conversations about a topic. I use Pandora stations for simplicity. Here are my go-to stations: John Mayer radio, Ed Sheeran radio, Colbie Calliat radio, and Jack Johnson radio.

4) Plickers: Jacob mentioned needing something to do. Plickers offers him the opportunity to show me what he’s been processing while fumbling with his phone and listening to me. I simply pose a multiple choice question, and the students hold up a personalized card indicating their individual answers. I use my phone and Plickers app to scan the room, and the app collects the answers and graphs the data for me. The website simultaneously does the same, and I can show the students the class’s data. The set-up is minimal.  Print the cards from the website. (10 seconds) Enter your students’ names. (5 minutes) Go to the “library” to create questions. (5 minutes)

Do you have games or other tools that get your kids excited about chemistry?  Share!

An Unexpected Source of Inquiry-Based Lab Practicals

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USNCO

Each spring my Local Section of The American Chemical Society (ACS) hosts a rigorous two part exam as part of the selection process for the The International Chemistry Olympiad (IChO) IChO is an annual international competition for the world’s top chemistry students. Each year, nations from all over the world will send teams of four to compete for top honors. The ACS sponsors the Olympiad program and helps select and train students for the competition which is held in a different participating country each July. As part of the selection process, the ACS administers the National Olympiad Exam to more than 1,000 students. Twenty of the top scoring students are selected to attend the two-week Olympiad Study Camp held in June at the Air Force Academy in Colorado.  

When my students ask how they can prepare for the local competition I direct them to the website of released past exams and tell them to download and practice answering the questions. Each national exam is separated into three parts. Part I is a multiple choice test consisting of 60 multiple choice questions and covers a wide range of chemistry topics, and Part II is an eight question free response test covering theories and models. Parts I and II can be downloaded and practiced at home. Part III, on the other hand, is a lab practical. This is the part of the exam that is difficult for students to prepare for on their own. It is also the part of the exam that I have used to create some of the most engaging and fun lab challenges to use in my classroom. They provide authentic learning experiences for all my students, but also help those taking the exam prepare for the lab portion.

The lab practicals on the exams are presented as problems. No procedure is given. Students must use their chemistry knowledge and lab experience to devise a plan and solve the problem. I like this format as it integrated nicely with the Modeling InstructionalTM methods I use in my class. The best part is that the released exams come with lists of materials and equipment, helpful hints to the proctors, and solutions! My students respond well to the format.  They approach each activity like a personal challenge. They brainstorm and bounce ideas off each other. They try different things and report back to each other - collaboratively trying to improve the protocols they design.  

I plan on adapting and incorporating more of these challenges in both my first year and AP courses next year.  

When logged in, registered members of ChemEd X can access the student and teacher files of the Density Challenge that I adapted from Part III of the 2001 exam at the bottom of the post.

 

Concepts: 

Density

Time required: 

45 minutes

Background: 
  • water and isopropyl alcohol solutions in labeled beakers

  • 2 10 mL graduated cylinders

  • 2 plastic pipettes

  • 4 test tubes large enough for your plastic object to fit inside

  • a bottle of distilled water

  • plastic object (recommended: a drywall wall anchor)

Procedure: 

Students will create a procedure to solve the given problem.

Preparation: 

This lab calls for 70% (not 91% or 99%) isopropyl alcohol which is sold as “rubbing alcohol” in most stores or pharmacies. You can use the cheapest brand available as long as there are no dyes, perfumes or additivies. Make sure the plastic sample you have chosen will fit in the test tubes and that the sample will float in water and sink in the alcohol. Students should wear lab goggles.  

Credits: 
Lucy Pryde Eubanks, Clemson University, Clemson, SC Chair Robert Becker, Kirkwood High School, Kirkwood, MO Craig W. Bowen, US Naval Academy, Annapolis, MD Nancy Devino, ScienceMedia Inc., San Diego, CA Sheldon L. Knoespel, Michigan State University, East Lansing, MI Steve Lantos, Brookline High School, Brookline, MA Jim Schmitt, Eau Claire North High School, Eau Claire, WI Robert G. Silberman, SUNY-Cortland, NY Christie B. Summerlin, University of Alabama-Birmingham, Birmingham, AL

Spring Fever, Stoichiometry and Specific Heat

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Smore

What am I doing to help kids achieve?

How do I know when they are there?

What is the evidence?

  From the looks of things, we are all in the same boat. Spring fever. I had two groups of students. Both are ending 3rd quarter, looking out a window at the first nice weather we have had in weeks. Most are already planning their spring break vacation and some have left early. Notice, not much talk about chemistry. The curriculum said it was time for stoichiometry for one group and specific heat for another. Just what the kids wanted to do (read with sarcasm).
  I pulled out an activity from an old friend, Bill Ignatz. The kids came in. My first question was, "Who wants to cook and eat smores in chemistry?" Hmmm...let's see...doing worksheets or eating chocolate, marshmallows and graham crackers? No surpise 99% of the kids wanted smores and were more than willing to beat up the one percent who voted "no" (not to worry...I nipped that in the bud..don't want the classroom to turn into a political campaign rally...). Here is the deal, each student had to provide me the exact amount of money it would cost me to buy all the materials at the store. Now, for most of my students I am convinced they eat about five meals a day and weigh about 10 pounds. To them, a smore would be like drinking nectar from the gods. Quickly the questions started coming. "How many students?" 56. "What makes up a smore?" I provided the "balanced equation" for a smore. One large graham cracker, one marshmallow and two small pieces of chocolate yields one smore. "How many graham crackers in a box? How many pieces of chocolate in a bar? What is the cost per box and package?" Pretty soon, we had a real live stoichiometry problem. Although we did not use traditional chemicals, it tasted better and the students used the same types of proportions, factor labeling and thought processes to solve the problem. We also had a tutorial on using bunsen burners. They had to successfully set the burner on fire and not their lab partner. I am happy to say, they succeeded. Overall, the majority of the students nailed the number ($16.86) and showed their work. Thanks Bill Ignatz...I know what some of you are thinking. Eating in a lab? I cleaned everything and sprayed all the tables down with a 10% bleach solution before the lab. I know I went rogue but it was worth it....
  Next came another group of students who were doing specific heat. They were tired and so was I. We had just found the heat of fusion of ice so they knew how to use a calorimeter (FYI - cheap garage sale coffee pots are great sources for hot water). I showed them what the materials they had available, said I would provide a metal and they had to find the specific heat and ended with "Good Luck". This lab is all over the internet. Students quickly found a reasonable procedure. The day after they got the data I put a wide variety of metals on the board with their specific heats and told them that they may have one of them. One student said that her specific heat was similar to one but her sample appeared to look like another. Another student decided to also take the density of the material as a second way to identify the metal. A third student thought that his specific heat was similar to silver so I must have given him about 60 grams of silver (hmmmm.....not likely...). Overall, the majority of the students did well.
     To use a baseball analogy, we are rounding third and heading for home.  It is difficult to teach during great weather and when kids are starting to dream of summer.  This can be a great time to have the courage to try new things and ask new questions...and maybe have a smore or two...

Lab Report Feedback, Part 2: Using a Comment Bank to Provide Student Feedback on a Lab

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I was sitting at my laptop marking up some labs and realized I had some students that kept making the same mistake as previous labs. So…this got me thinking. How can I get students to more carefully utilize my feedback? (This isn't a post to bash my students that aren't using my feedback. It's as much an indictment of how I structure feedback as it is of their lack of using the comments.)  I will describe for you a technique I have used previously - with some success - which I have re-adopted this year.

 

But let's go back in time a bit, to last fall. At that time I wrote a post about how I use Drawboard PDF on my Surface Pro 3 to provide written feedback to students on their lab reports. I still utilize Drawboard, but wanted to try using a slightly different means of providing feedback. So I revised a lab report Comment Bank I created a few years ago to make it more relevant to the new IB criteria for Internal Assessment. And while some of the comments might be quite specific to IB, the idea itself - and some of the comments included - might prove useful.

 

So now when I provide feedback on a student lab, I write comments that refer to an online Comment Bank that students can view. See the image below. In the image, there are three specific comments, Eval.4, Eval.23 and Eval.24. The specifics of these can be found in the online Comment Bank. I use a Google Form, because I can add a comment any time. I tend not to change the numbering system, even though I keep thinking I'd like to re-order them to be a bit more logical. But what happens is I think of a new comment and simply add it to the end of the list. If a student has a previous lab with a specific comment, I don't want to mess them up with a new numbering system.

 

 

Does it work? I find that this allows me to give more detail in less time. And the feedback actually includes some guidelines/advice for the students about how to fix the errors - which is something my students have requested previously. So when a student receives their lab report back, they go to the online Comment Bank for the details.

 

I've attached the same lab below that I shared (with student permission) in the fall with regular feedback. This time many of the comments could be made by referring to the Comment Bank.

 

My goal in using this method is two-fold. First, I'd like to be more efficient with my comments - and this allows me to streamline that process. Admittedly the first few labs in any marking cycle are a bit slower as I reacquaint myself with the Comment Bank. But once I get in a groove and start remembering the specific comment codes, the process becomes faster. My second goal - which I haven't implemented yet - is to have students keep track of the comments. So after a few lab reports, if a student is getting the same comments, I'd want them to recognize that and actually work to improve the next lab with respect to that specific comment - getting better with each lab report. I'm hoping to implement that next year and see how it goes. I'll provide an update if/when I make that happen.

 

As I'm still in the middle of the process with my current group of students, I'll be getting some feedback from them - and reflecting on their lab scores as well - to see how effective the process is for them. That will be shared in a future blog post.

 

How do you make comments for students? Have you ever used a comment bank or something similar? Do you have any suggestions for comments I should include?

 

 

 

 

Self-Healing Concrete

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Recently, I came across an article about self-healing concrete on the ACS Central Science open source journal website. Typically we think that the wear and tear of automobiles on the roads causes concrete roads to deteriorate, eventually causing potholes and requiring the use of patching. Regular maintenance, like patching, gets expensive over time. If we were to zoom in on a microscopic level we’d see microscopic cracks that allow in water, salts, and ice. Since ice has the ability to expand, the tiny little cracks will become big noticeable cracks.

 

Something interesting to note, according to the author’s reference of a Washington Post article, is that “concrete use is set to skyrocket, due to a building boom in countries like China, which used more cement from 2011 to 2013 than the U.S. used in the entire 20th century!” With this increased use of concrete being present, and the added carbon emissions during production, some researchers set out to create a biologically-based concrete that self-heals faster than normal (think bacteria). Apparently, concrete has the ability to heal itself but in an extremely slow manner.

 

The first example of bacteria used to induce self-healing properties comes from Professors Hendrik M. Jonkers and Erik Schlangen of the Delft University of Technology, in The Netherlands. They report a self-healing bioconcrete where “dormant bacterial spores contained in clay pellets germinate when cracks expose them to moisture. The microbes feed on calcium lactate to form limestone, sealing the cracks...in just 3 weeks…[and] gaps up to 0.8 mm wide.” The researchers have set out to develop a sugar-based component that would replace the expensive calcium lactate.

 

Neil De Belie, a structural engineer at Ghent University, in Belgium “packages bacterial spores in a melamine formaldehyde shell that has been able to make concrete that can heal small cracks up to 1 mm wide in 4 weeks. They’ve recently identified a limestone-producing bacterial strain that does not require oxygen, but instead uses nitrates.”

 

Thirdly, researchers are developing methods that involve hydrogels. The idea here being that hydrogels would water and nourish the bacteria, enabling them to live longer after germination. Plus, hydrogels do not need to be encapsulated, which make the concrete production process easier.

 

Additional research is being conducted with polymers; this research is still seemingly in its infancy.

 

Hopefully you’ll find some use for this article in your instruction whether it’s with properties of water, chemical reactions, or materials science.

Pick Attribution: 

Prachi Patel

Publication Date: 
Monday, December 14, 2015
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