Take-Home Quiz (Week #13)
Open Book, Groupie Part of Quiz

    You must get 30% of the points offered correct in order to be eligible for having your grade curved.

1. (10 pts) Jimmy ran the saponification reaction using a type of fish oil, and arrived at the results shown on Jimmy's data sheet. On the reverse side of this page, draw the structure of the fish-oil molecule he used.

2. (10 pts) Cheryl also ran a saponification reaction using a type of animal fat, and arrived at the results shown on Cheryl's data sheet. On the reverse side of this page, draw the structure of the animal-fat molecule she assayed.

3. (5 pts) Wilbie took some of Jimmy's fish oil and some of Cheryl's animal fat, warmed them both to 80°c (Cheryl's sample liquified) and sprinkled in some nickel dust into both samples and then bubbled hydrogen gas into both samples for a few minutes. He then turned off the hydrogen bubbler and also allowed the samples to cool back to room temperature. Cheryl's sample resolidified as expected, but this time Jimmy's fish oil also solidified. Why?
   
   
   
   
   
   

4. (15 Thinker's Points: can you go from what was given in class to something beyond that?) Finally Mary Lou bopped into lab late having been unsuccessful in finding a sample of fat or oil for her day's work. She presumed she might use some from one of her classmate's stocks. However, she found no one in the lab. Of course, she gravitated over to what she thought was her heart-throb's bench and saw two samples in the rack on his desk - one liquid and the other a gelatinous solid - both labelled "fish". But what to do with them? Of course, reading the class notes for directions was too reasonable a thing for her to do, so she looked around to see what might be available. Not realizing that Prof. Bengston was setting up for another class, she assumed that the small dropper bottle containing reddish "bromine" (Br₂) was for her use. At least she had enough sense to warm up the "jelly" tube so that its gelatinous contents liquified so that she could "borrow" a portion of it, as well as a little from the other tube. She then added a drop of the reddish bromine to each of her tubes, and swirled them. While the reddish color disappeared as it slurried into the oil in the first tube, the reddish color wouldn't go away in the warm tube. By this time her eyes and nose were running due to the irritation caused by the bromine fumes, and so she retreated to the ladies room to wipe her eyes and blow her nose. When she returned, she found her brother Jason and his friend Wilbie all excited and standing at Jimmy's desk - but both were also teary. "Who did this? It's great!" sniffled Jason. He added another drop of bromine to the uncolored oily tube and the color again quickly disappeared. (The other tube had cooled and was now a reddish gel.) Wilbie wheezed : "I brought Jason here to show him all the hard work I did this afternoon. But, boy! This is a lot easier than what I did." Of course, Mary Lou took credit for the great discovery although she had not the slightest idea what all the excitement was about. Help out Mary Lou. Describe to her why the red color disappeared in the oil and not in the hydrogenated oil. Perhaps a chemical reaction equation might be useful!
   
   
   
   
   
   
   
   
   
5. (10 easy points) Draw the structure of the shock-sensitive explosive viscous liquid "nitroglycerin," and tell why Alfred Nobel became so famous with regard to nitroglycerin.