MU, Chemistry 8160 - Organic Spectroscopy - Fall 2010


              E4Q1   E4Q2   E4Q3   E4Q4   E4Q5    E4   Assig.  COURSE
Max. Poss.    15.0   15.0   20.0   20.0   30.0  100.0  200.0   100.0%		
Average       11.2    6.5   18.4          12.2   60.4  182.4    75.6%
Std. Dev.      3.0    5.3    2.3           5.7   13.9   12.6     6.8%
Minimum        6.0    0.0   12.0    0.0    2.0   42.5  156.6    63.6%
Maximum       15.0   15.0   20.0   20.0   23.0   86.3  196.6    87.7%

Q1 went very well, Q3 went much better than expected, Q2 and Q5 went so-so, 
and Q4 was quite a bust.  Q4 was not counted and your final grade is your
percentage based on Q1 - Q3 & Q5.  

Q4 was not counted because the average of those students who worked Q4 was 
below the acceptable threshold of 50%.  The averages of Q2 and Q5 are above 
50% considering the students who worked the problems.

Regarding Q2:  Most got the C-signals of ethyl acetoacetate correctly 
assigned and that was nice to see.  There was some confusion about the 
minor component (one of the two a priori possible enols).

Regarding Q5:  We dealt with several pyridines in Assignment A10 and I had 
hoped that would make nicotinic acid a fair question.  To do this right one
must know that OH groups can be all the way down to 2500 1/cm in aromatic 
acids!  Whether the acid is in the 2- or 3-position is a little hard, but 
it is easy to exclude the acid in the 4-position.

Q4 looks very complicated.  The trick is not to start with the analysis of 
the spectra until after you decided what to look for!!  You are half way there
once you understand that the CH is a chiral center and that its chem. shift 
and coupling are key. The CH must be coupled to NH in all isomers and it is 
coupled to only one CH2 in two isomers.  The rest is chem. shift considerations. 

The average for Exam #4 is 60.4%; a little lower than expected but 
acceptable considering the comprehensive nature of the final.

The course average was determined as described in the syllabus (your 10 best 
assignments for a maximum of 200 points, 3 tests @ 100 points max. each, the 
final counts twice).  The course average is 75.4% and that is quite perfect 
from my perspective. The average deviation for the course is 7% and that also 
is very much in the desired range.  Twelve students are above 65%, one is at 
64% and close to 65%, and no "C" grades are given. "A" for average or better 
(8) and "B" otherwise (5).