CLASS NEWS

Course announcements are generally made in class. Some of them are also compiled here and sorted by date. Since students may not check this page frequently, urgent announcements are made by email.

11/27/06 - FINAL LAB NEWS. 1) Do not turn in your lab notebooks with your lab reports. You will need your notebook next semester. 2) As of today, no lab experiments remain for the semester. 3) As of today, no lab lectures remain either. 4) Lab report for expt #5 (carvone isomerization) is due Mon, Dec 4. Attach all spectra to your lab report and carefully label them. Instructions for spectra and report were posted 11/13/06 (see below). GOOD LUCK WITH THE REST OF YOUR SEMESTER.

11/20/06 - NMR Workshop III. 1) Do workshop assignment. 4) The two spectra: styrene oxide (full) | 4-hexen-3-one (full) | both compounds (expanded) 5) NMR tables from lab manual.

11/13/06 - Lab report for expt #4 is due Mon, Nov 27. Attach all spectra to your lab report and carefully label them. The minimal spectrum list includes these NMR spectra: 1) full spectrum of mixture, 2) full spectrum of TOP, 3) useful expansions of TOP, 4) full spectrum of BOT, 5) useful expansions of BOT. You may also have collected IR spectra of TOP and/or BOT. If you have, attach them to your report.

The instructions for this report suggest including a hand-drawn figure showing your most conclusive TLC data. If you do this, please draw a single figure showing all of your TLC data. This means you will have to combine data from different TLC plates to "compose" this drawing (note: it is not kosher for scientists to combine data in this way), i.e., the drawing will make it look as if all 6 reference compounds were compared to your mixture on a single plate.

Calculate %recovery by comparing the weight of a purified sample to the weight of the starting sample. 0.1 g of recovered material and 0.4 g of starting material means 25% recovery. Calculate e-yield for the column only. Guess the weight of your silica gel and estimate the weight of the solvent you used. The amount of product is the combined weights of the two purified compounds.

11/13/06 - Carvone isomerization lab. Instructions will be given out in class (download). FT-IR of carvone (starting material). FT-NMR of carvone (starting material).

11/9/06 - No lab lecture this week, Th, Nov 9. I may make some changes in the lab calendar. As things currently stand, we are scheduled to spend the next two weeks working on the NMR spectra of your unknowns. (Actually, we are supposed to wrap that up next week and not have lab the week of Thanksgiving.) Instead of working on NMR spectra next week, I might have you start a new experiment instead. I have not chosen one yet, and it is already Thursday, so the chances are slim. If I do schedule a new experiment, I will provide instructions in lab. No preparation on your part before lab will be required. Whichever option I take, next week's lab session will be relatively busy. As always, please arrive on time and prepared to work.

10/30/06 - No lab lecture this week, Th, Nov 2. I believe Ron plans to schedule a pre-exam help session for Th evening, so don't plan on hitting the bars until Friday. Dan and I will use the start of lab the following week, M-W, Nov 6-8, to cover vital lab info. Please be on time.

10/26/06 - Lab opens early this week, M-W, Oct 30-Nov 1, to facilitate the dry flash column chromatography experiment. You can enter the lab at 12:30 and begin work by 12:40. Lab will close at the usual time, 5:00 pm.

10/26/06 - Revised lab reports for experiment #3 are due Monday, Oct 30.

10/9/06 - NMR Workshop I Activities. 1) Review presentation on NMR spectroscopy or read NMR Quick Facts. 2) Read NMR Processing Hints. 3) Do workshop assignment. 4) The three spectra: p-anisaldehyde | 2-bromopropane | 2-butanol 5) NMR tables from lab manual. 6) SpinWorks manual

10/5/06 - NMR lecture notes from Oct 5 lab lecture can be downloaded here.

10/5/06 - IR spectrum of isopentyl alcohol can be downloaded from Sigma-Aldrich here. IR spectrum of acetic acid can be download from the Infrared Petting Zoo here.

CONTEST !!! (Contest closed on 10/11. Winners are Mariah Federow & Emily Warschefsky. Congratulations!) I will buy a cup of coffee/tea for the first two students who can tell me the correct name of the song that the Petting Zoo plays when you view the acetic acid spectrum on their site. No, it's not Peanut Butter Jelly Time. If you don't know the name of the song, you can still win! Just sing the words that are chemically meaningful. (To be elgibile, you must be a Chem 201 student in 2006. One entry per student. Entries must be submitted no later than Halloween 2006.)

10/5/06 (revised 10/12/06) - Lab notebook and reports for experiment #3 are due Friday, Saturday, Oct 14. I had announced other dates, but Saturday is my (current) story and I'm sticking to it. Important: Staple your GC, your IR spectrum, and your NMR spectrum to your lab report. Put the report in your notebook and put the notebook in my ground floor mailbox (do not use the plastic box next to my office). Pay careful attention to the arcane instructions for reporting IR and NMR data (full details are given in the lab manual appendix).

10/5/06 - No lab lecture on Oct 12. The following week is Fall Break. We will resume lab work on Monday after Fall Break by performing the TLC portion of the Chromatography experiment. Some of the procedural details will be explained in lab at the beginning of the session (be on time). Many web pages describe how thin layer chromatography works and how to perform TLC experiments in the lab. Here is a sample: Wikipedia | Colorado Univ. Lab Techniques | Journal Chemical Education

10/2/06 - IR Workshop Activities. 1) View presentation on IR spectroscopy. 2) Workshop assignment. 3) The five spectra: elirtinozneb3fcsib53 | narypordyhid | lonaxeholcyc | enonaxeholcyc | enilina 4) IR tables from lab manual

10/2/06 - New lecture location. All lectures, morning and evening, are moving from Psych 105 to Eliot 314 for the rest of the semester. Ron will give you the schedule for the morning lecture. Lab lecture will be in Psych 105 on Oct 5, and Eliot 314 on Oct 12 (and thereafter). Eliot 314 has windows, two projection screens, and white and black boards. It also happens to be the "original" location of o chem lectures (before the current Psych auditorium was constructed).

9/30/06 - Lab report #2 revisions are due 6:40 pm Thur, 10/5. Revision is necessary only if your report was marked unsatisfactory. In most cases, you do not need to rewrite your report, you just need to add a few data or an explanation to the existing report. Contact me if you are unsure what I am looking for in the way of a revision (email is ok, in person is better, and you need to remind me what was wrong with your first draft).

9/27/06 - Lab next week begins 1:10 sharp in computer lab (Chem 203). Please read Carey 13.20 (Infrared Spectroscopy) before coming to lab. We will spend roughly an hour in the computer lab learning about, and practicing reading, IR spectra. Then we will move to the wet lab next door and finish Experiment #3. Remaining activities include: distillation of product, weighing of product, GC of product, IR of product, preparing and submitting an NMR sample of product.

9/27/06 - No lab lecture on Thursday Sept 28. See other announcements for information about next lab.

9/21/06 - Get info on gas chromatography (GC). I forgot to lecture on GC tonite, so here is a brief summary of how GC works and how you analyze your data:

You have all seen & operated our GC by now. Basically, 1) you inject your sample into a stream of hot moving gas (carrier gas) , 2) the gas (mobile phase) pushes your sample through a thin metal column packed with oil-coated powder (stationary phase), 3) different compounds in your sample are absorbed by the oil to different degrees, and once absorbed, they re-vaporize into the moving gas at different rates; thus, the "column" retains some compounds more than others, 4) an electronic detector measures the composition of the gas flow leaving the column; whenever the carrier gas is contaminated with one of your compounds, a "peak" is drawn on a piece of moving chart paper.

The GC data from a 2-compound mixture might look like this:

(note: this excellent picture is being borrowed from the University of Akron's most excellent, and incredibly detailed, web site on chromatographic methods and is used here without their permission)

The data in this drawing starts on the left (time 0) with an artificial mark that shows when the injection was made. The first compound to exit the column appears as a small peak. The time it took for this compound to transit the column (the retention time) is tm. The second compound to exit appears as a much larger peak (there is more of this stuff in the sample) with a retention time of tr.

Step #1. Identify your compounds by comparing their retention times to the retention times measured for a known sample (posted on the door of Chem 209). Hint: your absolute times may not match those in the known sample, but your relative time, tr', should match one of the relative times in the known sample.

Step #2. Determine the purity of your sample by comparing the sizes of the different peaks. Peak area is what counts, not peak height, but the two are usually correlated.

9/21/06 - Get more info on separatory funnels (and view good movies) at a web site sponsored by Santa Fe Community College. I showed only 3 movies in lab lecture: filling a sep funnel (2.9 MB), mixing & venting a sep funnel (7.9 MB), and draining a sep funnel (4.7 MB), but the SFCC site contains much more info and 3 more movies! (Note: the fill-mix-drain movie links given above will download movies from our course web site so downloads will be fast; I am going to remove these links at the end of next week because I did not obtain a copyright for these movies.)

9/21/06 - Lab notebook & report for expt #2 are due at the end of your lab session. Make sure you attach gas chromatograms (yours + your partner's; fully annotated as figures in a scientific document) to your report.

9/21/06 - Lab report #1 revisions are due 6:40 pm Thur, 9/28. Revision is necessary only if your report was marked unsatisfactory. Contact me if you are unsure what I am looking for in the way of a revision (email is ok, in person is better, and you need to remind me what was wrong with your first draft).

9/21/06 - Pre-lab assignment for experiment #3. Download this assignment: pre-lab #3. This assignment requires access to the on-line lab manual. It is due at the start of your lab session next week.

9/15/06 - Lab notebooks are due at the end of your lab session next week. Leave your notebook in the cardboard box by the lab door. Make sure your name and lab day are printed neatly on the cover of your notebook. When I have finished looking at your notebook, I will send you an email and place the notebook outside my office door, Chem 408.

9/15/06 - Expt #1 lab report is due by 5 pm, Mon, Sept 18, in my Chemistry box. My box is located next to the secretary's office, Chem 303.

9/15/06 - Pre-lab assignment for experiment #2. Download this assignment: pre-lab #2. This assignment requires access to the on-line lab manual. It is due at the start of your lab session next week.

9/7/06 - View an on-line demo of a melting point measurement. The organic chemists at the University of Akron have put together an on-line demo of two interesting melting point experiments. Wikipedia will tell you what a eutectic mixture is (and why it is called eutectic). They also explain why a compound's melting point may not always be the same as its freezing point.

9/1/06 - Pre-lab assignment for experiment #1. Download this assignment: pre-lab #1. This assignment requires access to the on-line lab manual. It is due at the start of your lab session next week.

8/21/06 - Special room for Sep 7 lab lecture. Because of psychology-related festivities that are going on in Psych 105 on Thurs, Sep 7, our lab lecture will move to Bio 19 for one nite only. We will be back in Psych 105 on Sep 14.

8/14/06 - New 201 lecturer for 2006. (see Course Info: Instructors) Ron McClard will be the Chem 201 lecturer for 2006 and will issue lecture materials and course instructions in class. Do not download or rely on lecture materials posted at this web site unless Ron instructs you to do so.

Alan Shusterman will continue as the Chem 201 lab instructor for 2006 and will continue to update the lab materials at this web site and post lab-related news announcements.

8/14/06 - Lab Qwik-Start. All lab sections will meet the first week of classes (Aug 28-30) for safety orientation, lab check-in, and so on. There will also be a lab lecture on Thurs, Aug 31.
 
If you expect to earn lab credit for Chem 201, you must attend one of these lab sessions and complete the safety orientation and lab check-in, whether or not you have already registered for a lab session.