Kinetics Explorer: an interactive web-based resource for teaching kinetics at the first-year college level Bob Hanson St. Olaf College, Northfield, MN BCCE 18, July 20, 2004

Goals of this Presentation Briefly describe the context of first-year chemistry at St. Olaf. Describe the goals of the project. Demonstrate the project. Explain the textbook-problem motivation for this project. Share some student feedback.

First-Year Chemistry At St. Olaf Stoichiometry gas laws pKa/pKb/Ksp Stoichiometry gas laws pKa/pKb/Ksp Molecular Structure Bonding Thermodynamics Electrochemistry Kinetics Molecular Structure and Bonding Chemistry 125 Chemistry 121 Chemistry 123 Chemistry 126 FALL INTERIM SPRING

…for about 8 weeks we study thermo… Thermodynamics Electrochemistry Kinetics Chemistry 126 More about this later this morning and at S574 (Wed. 2:50)

…for about 2 weeks we study electrochemistry… Thermodynamics Electrochemistry Kinetics Chemistry 126

…for the final 3 weeks we study kinetics. Thermodynamics Electrochemistry Kinetics Chemistry 126 ?

The Problem: Only about 2/3 of the students (130) had a textbook from the previous class. Should we write one ourselves? Maybe this could be more fun… Should we make the other 70 students buy a $120+ textbook for a 3-week segment?

How about a Web Site?

The Idea: Kinetics is dynamic. Kinetics lends itself to discovery-mode learning. Kinetics involves mechanistic hypotheses. Kinetics is experimentally based.

Maybe this could be really fun: Could using web-based dynamic media provide greater opportunities to dig deeper into kinetics? To discover relationships in a more straightforward manner? To explore more fully concepts that otherwise are just “givens”?

The strategy: Reuse successful components made with JavaScript… JavaScript Kinetics Simulator IMT Concept Index JavaScript DivGraph Module OK, maybe not THAT easy, but…

The result: It was worth the work!

We divide kinetics into two basic sections…

We start with thinking about time as a variable in chemical reactions…

We discuss the ideas of reaction rate, rate law and reaction order.

We talk about the effect of temperature in terms of energy levels and probability.

We discuss the ideas of reaction mechanism and elementary steps—“fast” and “slow.”

And we have some fun with some more complex examples—some “break the rules.”

Along with all this, we have “explorations.”

Within each topic, students can explore the concepts in depth and decide for themselves.

Lots of graphing and graphical analysis is involved in kinetics.

Students explore the effect of different aspects of mechanism on reaction rate.

We often connect these explorations with actual lab experiments or demonstrations.

An “exploration” is an interactive simulation of a chemical reaction that runs in real time, at the student’s pace, and offers an opportunity to learn while playing. The student is encouraged to experiment and to think about a few questions that relate to the experiment. So what’s an “Exploration”?

For example…

Everything from the simple…

…for the standard analysis…

…to the more complex…

If we double the initial [NO2], then the initial rate should…

…to the more complex… …quadruple!

…and beyond!

…with dynamic graphing of data…

…and dynamic rate law definition.

presentation continues with a demonstration using the actual site (if time and the internet gods permit) at

2003 Feedback from students… “The unity of the topical sequence throughout the semester was especially well thought out. Additionally, this class made the best use of computer programs and web resources for true learning that I've ever encountered.” “Try not to lean so heavily on the web pages as teaching materials. I had a hard time navigating them. Also, I had to download Netscape (which I don't really mind) however, for some students, full-time computer access is hard.” “Please make the Kinetex website a text book, it was very hard to really study the material when it was on line. When I study I make notes in the margins so it was difficult to do so online! (this accounts for the low score on the online reading question) Otherwise the other web material was wonderful!!!!” “I think the Kinetics Explorer online is horrible for text book use. I really like the quizzes and supplemental programs, but would much prefer a paper book for this chapter.

2004 Feedback from students… It was very helpful. It was all that I used when learning Kinetics. To be honest, i really liked it. it really supplemented the textbook and laid out what was important. It was very helpful- I consulted it instead of the book when I had questions. it wasn't as interesting as thermodynamics or electrochem. it was harder too. the rate law stuff and k were not easy concepts The online kinetics material was helpful in understanding the big concepts, otherwise it was not helpful for homework or test preparation. I felt that the lecture was based on the online material and it was not very helpful to go back and do the explorations again.

2004 Feedback from students… They were very beneficial. I used it a lot more once I decided I needed to get more serious about the course. I think it paid off. loved it...understood how to use it and it was better than the supplement. I thought the online material for the kinetics was very beneficial. I used it often and thought that it was very well done. I thought the online material was quite good. One thing that might be helpful would be more examples to help us understand homework and plugging in numbers to these equations..

Conclusions: Students at St. Olaf appreciate web-based materials as supplements, not as primary reading. The dynamic nature of JavaScript-driven web applications nicely matches the dynamic nature of kinetics. Kinetics simulations allow a deeper understanding of kinetic phenomena.

Thank you! feedback appreciated Bob Hanson St. Olaf College, Northfield, MN BCCE 18, July 20, 2004