teaching substitution and elimination with real life examples l.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Teaching Substitution and Elimination With Real-Life Examples PowerPoint Presentation
Download Presentation
Teaching Substitution and Elimination With Real-Life Examples

Loading in 2 Seconds...

play fullscreen
1 / 48

Teaching Substitution and Elimination With Real-Life Examples - PowerPoint PPT Presentation


  • 552 Views
  • Uploaded on

Teaching Substitution and Elimination With Real-Life Examples. Bob Hanson St. Olaf College, Northfield, MN http://www.stolaf.edu/people/hansonr 20 th Biennial Conference on Chemical Education Indiana University July 29, 2008. Road Map for This Presentation.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Teaching Substitution and Elimination With Real-Life Examples' - Olivia


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
teaching substitution and elimination with real life examples

Teaching Substitution and Elimination With Real-Life Examples

Bob Hanson

St. Olaf College, Northfield, MN

http://www.stolaf.edu/people/hansonr

20th Biennial Conference on Chemical Education

Indiana University

July 29, 2008

road map for this presentation
Road Map for This Presentation
  • Background: Data-Driven Chemistry
  • The Course: 1st Semester Organic
  • The Data: 39 reactions
  • The Exam: 25 questions
  • Conclusions
slide3

Background: “Data-Driven” Chemistry

generate data

analyze data

extrapolate hypotheses

generate hypotheses

slide4

Background: “Data-Driven Chemistry”

  • Start with raw data
  • Transform the data into meaningful information
  • Create a working model

R. M. Hanson, S. A. Bergman,

"Data-Driven Chemistry: Making Molecular Models (Literally)

from Electron Diffraction Data”, J. Chem. Educ.1994, 150

slide5

Background: focus on analysis

analyze data

(identify trends)

generate data

(experimental)

generate hypothesis

(explain shapes

and trends)

extrapolate hypothesis

(predict shapes)

slide6

Application: organic chemistry

analyze data

(identify trends)

generate data

(experimental)

generate hypothesis

(explain reactions)

extrapolate hypothesis

(predict reactions)

the course
The Course

1st semester of a standard two-semester course

55 students in my section (approx. 120 students total):

39 sophomores

13 juniors

3 seniors

Textbook: Paula Bruice, Organic Chemistry, 5th ed.

slide11

Focus: substitution and elimination

analyze data

(identify trends)

generate data

(experimental)

generate hypothesis

(explain reactions)

extrapolate hypothesis

(predict reactions)

data sources
Data Sources

Ingold, Structure and Mechanism in Organic Chemistry, 2nd Ed., 1969

Compendium of Organic Synthetic Methods, 1971

M: March, Advanced Organic Chemistry, 3rd Ed., 1985

V: Vogel, Textbook of Practical Organic Chemistry, 5th Ed., 1989

the exam
The Exam
  • 55 minutes
  • 25 multiple-choice questions
  • Instructions:
  • In each case, read each possible answer, use a process of elimination, and circle the BEST answer. If you are having trouble deciding between two answers, briefly explain your final choice. If you do so, use just a few words, just to clue me in to what you are thinking. Do not dwell on any particular problem for an extended period of time. Each question is worth 2 points.
the exam40
The Exam

average score: 75%

(average exam score for the semester: 73%)

three additional questions

the exam41
The Exam

This test was:

(a) Easier than I thought it would be.

(b) Somewhat harder than I thought it would be.

(c) WAY harder than I thought it would be.

the exam42
The Exam

This test was:

(a) Easier than I thought it would be. 15

(b) Somewhat harder than I thought it would be. 14

(c) WAY harder than I thought it would be. 1

(d) Maybe a bit harder. 1

(e) About as hard as expected. 16

(f) Not too bad. 1

the exam43
The Exam

I think looking at the data this way…

“…is GREAT, I learned a lot!”

“…seems to apply to the real world

more so than the book.”

“…makes for an interesting way of learning

about these reactions.”

“…really works with the way I think. I liked it a lot!”

the exam44
The Exam

I think looking at the data this way…

“…is GREAT, I learned a lot!”

“…seems to apply to the real world

more so than the book.”

“…makes for an interesting way of learning

about these reactions.”

“…really works with the way I think. I liked it a lot!”

“…you can see and think through all parts of the

reaction, doesn’t feel as much like memorization

and regurgitation of info…you can think through

why an answer is right or wrong in comparison with

others.”

conclusions 1 3
Conclusions 1/3
  • For the most part, students “got it.”
  • Generally, students did not have trouble with the
  • definitions of SN1, SN2, E1, and E2.
  • A significant number of the students were still having
  • trouble identifying strong and weak bases.
conclusions 2 3
Conclusions 2/3
  • Stereochemical concepts and notation were integrated
  • into 6 of the 25 questions (24%). For these questions, 77%
  • of the responses were correct.
  • However, proper axial/equatorial analysis was critical
  • for 4 of those 6 questions, and for those, the average was
  • somewhat lower – 68%.
conclusions 3 3
Conclusions 3/3
  • Using a data-driven approach can work in organic chemistry.
  • Students rise to the challenge of guided inquiry.
  • Substitution and Elimination are still difficult concepts!
slide48

Thank you!

This presentation is available at

http://www.stolaf.edu/depts/chemistry/bh/bcce20