1. Class admin Turn in revision exercise #2
Pick up and fill out TA evaluation forms
Pink = Adrienne
White = Khadine

2. Oxygen uptake by Co(salen)
Notes on part 2 of lab:
Bring stopwatch
Depending on yields, may carry out project as a group

3. Last week: prepared Co(salen)
Co(salen) can bind oxygen, just like the biological heme molecule
easy
hard
versus

4. Oxygen binding depends on Co environment
Mercury view
In crystals:
Solvated:
Co(salen) exists with Co in a 4, 5, or 6 coordinate site
Solvated Co(salen) will bind O2 when it is 5 or 6 coordinate

5. Experimental apparatus
Which way will the water move?
How many SF’s to report?

6. Graphing data What is our: dependent variable independent variable
Which one belongs on which axis?
How do we best extrapolate to infinite time?

7. Revision exercise #2
Goal: submit an improved version of your lab 6 (MIMT) report
Take your report to the University Writing Center for feedback in paper and electronic form [computers available there]
You can skip the “Questions” section in your re-write – please focus on the report text (Title, Introduction, Data Analysis, Discussion)
Turn in your original and revised lab reports to me, with UWC comments if they are available
Due date: Class period on April 30th (two weeks from today)
Note: no other lab report is due that week
Hours for University Writing Center:
Mon-Wed: 10 AM – 10 PM
Thur: 10 AM – 7 PM
Sun: 2 PM – 7 PM
Web site:
Located in the Learning Commons of the WE DuBois Library

8. Writing exercise Experimental assignment Communication error
My intent: spend extra time revising the writing
(conciseness, organization, flow, transitions, paragraph divisions, grammar, readability, style)
Student interpretation:
GRAMMAR
Grading – positive points
Will reward effort
Will reward accomplishment

9. Evaluation of writing in course
How useful were the lectures on writing
Extremely Very Reasonably Somewhat Not at all
How useful were the TA comments on writing on the lab reports
How useful were the instructor comments on lab report 5
How useful were the UWC comments on writing the lab reports
Comments for improvement on the writing aspects of Chem242

10. NA exercise 25 pts / problem
-10 if SF errors
-5 unit errors
25 pts for group work (consistency in answers)
Positive points only.
(Divide points by 10, score will be added to lab 8 grade)

13. Experimental Recrystallization Anaerobic environment
Solvent temperature – entropic arguments
Evaporation – effect on purity?
Solvent choice (high relative solubility for impurities)
Recrystallization should be done relatively slowly
Anaerobic environment
vacuum
pump / fill cycles

14. Coordination of metals in inorganic compounds
Coordination Number
“dentate”