1. Green Chemistry Using the web-based Green Chemistry Assistant to enhance understanding of chemical reactions and processes Robert M. Hanson, Paul R. Campbell, Marc A. Klingshirn, and Gary O. Spessard St. Olaf College Northfield, MN 55057 hansonr@stolaf.edu 19 th Biennial Conference on Chemical Education, Purdue University Aug 3, 2006

2. Green Chemistry Green Chemistry Definitions “The utilization of a set of principles that reduces or eliminates the use or generation of hazardous substances in the design, manufacture, and application of chemical products.” -- Anastas and Warner; Doxie and Hutchison. “The design of chemical products or processes to reduce or eliminate the use or generation of hazardous substances.” -- Tundo and Anastas, Green Chemistry: Challenging Perspectives, 2000.

3. Green Chemistry Three Levels of Green Chemistry Processes www.shelldeerpark.com/chemical.htm

4. Green Chemistry Three Levels of Green Chemistry Reactions http://www.uncw.edu/smec/gk_fellows/askscience.html

5. Green Chemistry Three Levels of Green Chemistry Equations HCl (aq) + NaOH (aq)  NaCl (aq) + H 2 O (l)

6. Green Chemistry http://fusion.stolaf.edu/gca http://fusion.stolaf.edu/gca/goc1.htm http://fusion.stolaf.edu/gca/goc2.htm http://fusion.stolaf.edu/gca/goc3.htm

7. Green Chemistry http://fusion.stolaf.edu/gca/goc1.htm

8. Green Chemistry http://fusion.stolaf.edu/gca/goc2.htm

9. Green Chemistry http://fusion.stolaf.edu/gca/goc3.htm

10. Green Chemistry Green Chemistry Assistant http://fusion.stolaf.edu/gca Lessons learned: Students need help just writing the balanced chemical equations. Process is important, as most real experiments involve more than one process step.

11. Green Chemistry Green Chemistry Assistant http://fusion.stolaf.edu/gca Lessons learned: Lab manuals could be more explicit in guiding students to an understanding of the overall set of process steps they will be doing in lab.

12. Green Chemistry Green Chemistry Assistant http://fusion.stolaf.edu/gca Question: What is the balanced chemical equation for this reaction?

13. Green Chemistry Green Chemistry Assistant http://fusion.stolaf.edu/gca Is it this?... (atom economy = 88%)

14. Green Chemistry Green Chemistry Assistant http://fusion.stolaf.edu/gca …or this? (atom economy = 66%)

15. Green Chemistry Green Chemistry Assistant http://fusion.stolaf.edu/gca Question: What is the balanced chemical equation for this reaction?

16. Green Chemistry Green Chemistry Assistant http://fusion.stolaf.edu/gca Question: Is this one reaction or two?

17. Green Chemistry Green Chemistry Assistant http://fusion.stolaf.edu/gca Question: What is the atom economy?

18. Green Chemistry Green Chemistry Assistant http://fusion.stolaf.edu/gca Overall Atom Economy = 60%

19. Green Chemistry Green Chemistry Assistant http://fusion.stolaf.edu/gca Overall Atom Economy = 72%

20. Green Chemistry Green Chemistry Assistant http://fusion.stolaf.edu/gca In practice, Step 3 is important!

21. Green Chemistry Green Chemistry Assistant http://fusion.stolaf.edu/gca Lessons learned: Getting students thinking about the overall process is good. Expecting them to do it on their own because it’s “simple” is asking too much. The Green Chemistry Assistant enables us to explore the nature of green chemistry processes and green chemistry measures.

22. Green Chemistry  Faculty  Gary Spessard, Marc Klingshirn, Paul Jackson  Students  Paul Campbell, Allison Christensen, Elizabeth R. Johnson, Tim Barker, Tyler Drake, David Harris  Technology Support  Dan Beach  Financial support  WM Keck Foundation  Howard Hughes Medical Institute Green Chemistry Assistant http://fusion.stolaf.edu/gca