last updated Friday, October 31, 2014

Problem set  Meeting 11 

Announcement

1. Quiz 5

Quiz 5 will be administered on Tuesday, February 10, 2015 at 9 am. It will cover the entire lidocaine project.

2. Post-lab report for 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 February 12, 2015 or February 13, 2015 in your regular lab section. The report has to be written in the lab notebook and is worth 15 points.

3. Grignard Project

a. The Grignard project will start on February 10 or February 11, 2015.

b.The instructor will provide an in-lab demonstration of the Grignard setup (setup, heating, etc.) on Monday, February 9, 2015 at 4:00 pm in YH 6086. Attendance in this demonstration is voluntary (no credit) and is highly advisable for students that feel intimidated by the larger setup. Part of the demonstation will already discussed in lecture prior to this in-lab demo, but certain aspects like heating cannot be shown in the lecture.

4. Research project (Week 9)

a. Please look start looking for a partner for the Ferrocene project. Your partner should be in a different time slot than yourself i.e., if you are in the T/R afternoon section, try to find somebody in the W/F afternoon section. This way nobody has to put in additional time outside their regular schedule, which means that each group has four lab meetings to complete the project. We have to avoid as much as possible to have the entire class running around in the lab (Safety!). Note, since we have an odd number of students in the class, one student will work alone.

...and now back to the chemistry part of this course....the homework questions due on 2/10/2015 or 2/11/2015

1. Referring to the Grignard reaction, answer the following questions. Show balanced chemical equations when appropriate.

a. The presence of water poses a significant problem in this reaction. How is its presence minimized?

b. Which observations should the student make if the reaction initiated?

c. What is used to heat the reaction mixture?

d. Why is it crucial to add the ethereal bromobenzene solution at the proper rate? What is the student looking for here?

e. What is dry ice? Which precaution have to be taken when handling it?

f. After the reaction mixture with dry ice, the mixture was allowed to warm up, chipped ice and concentrated sulfuric acid are added. Which purpose does this step serve?

g. The combined organic layers are extracted with sodium hydroxide solution. Which layer contains the product then? In which form?

h. How is the final product recovered from the solution obtained in g.?