last updatedThursday, May 06, 2010
Problem set Meeting 11 Announcement
1. Formal Report
Make sure that you turn in a hardcopy of your research paper by Friday, May 7, 2010 at 4:30 pm and the electronic version to turnitin.com as well (CourseID: 3153616, Password: Chem30CL for Spring 2010 (no spaces!)). Late reports will be deducted points (10% per day including the weekend). If you do not submit the report online by Monday, May 10, 2010 at 10 pm, you will receive a "zero" score for the paper. In addition, it will be reported to the Dean of Students for attempted cheating. Any plagiarism, partial or full resubmission of a papers or/and other forms of cheating will result in a report to the Dean of Students as well. Make sure that you cite your sources and use your own words. Here is a checklist what should be included into the report. If you have any questions, please contact your TA or instructor asap, and not an hour before the submission deadline. The final version has to be submitted in a report cover! Loose paper collections, large binders or any kind of folders will not be accepted!!!
2. Lidocaine Project
a. The postlab report for the lidocaine project has to be written in the lab notebook and submitted to the teaching assistant. The due dates are May 11, 2010 and May 12, 2010 in your regular lab section. The report is worth 15 points.
b. The final product of the lidocaine project has to be turned in to the TA by Wednesday, May 5, 2010 at 4 pm for evaluation by the instructor. Late submissions will not receive any credit. Please note that the instructor will analyze the product if there is any doubt about its identity. Attempts to submit anything but your own lidocaine will be regarded as cheating which will be appropriately dealt with. Make also sure that you label the vial properly.
3. Grignard Project
a. The project will start on May 6, 2010.
b.The instructor will provide an in-lab demonstration of the Grignard setup on Wednesday, May 5, 2010 at 4 pm in YH 6086.
...and now back to the chemistry....the homework questions (due 5/6 or 5/7)
1. Referring to the Grignard reaction, answer the following questions. Show chemical equations when appropriate.
a. The presence of water should be minimized as much as possible during the formation of the Grignard reaction. Why?
b. Why is it necessary to further dry the glassware even though it looks dry? How is this accomplished in the lab?
c. Like many metals, magnesium is coated with a more or less thick oxide layer. Which problem does this pose? How is this problem solved in the lab?
d. Why is it important that the addition of the bromobenzene solution is carefully controlled? What is the student looking for here?
e. After the formation of the Grignard reagent is completed, the solution is cooled and then added to dry ice. Which purpose does this step serve?
f. After the mixture is warmed up to room temperature, chipped ice and concentrated sulfuric acid are added as well. Which purpose does this step serve?
g. The organic layer is extracted with sodium hydroxide solution. Explain briefly why. Which layer contains the product at this point? In which form?
h. How is the product recovered from the solution obtained in g.?