Chem. 30B Name _____ ___________________

Exam #2 please print

April 21, 2003 75 min. 105 points

Please choose a random 4 digit number for on-line scores ___ ___ ___ ___ .

Remember it!

Model kits may be used. Some questions have more than one correct answer, but you may give only one. Avoid crowding your answers. Use the back if needed.

1. Fill in the blanks:

[2] a. The functional group that is hydrolyzed (broken down) when starch is digested is

.

[2] b. The opposite of a hydrolysis reaction is a reaction .

[2] c. The most common sugar unit in the world is .

[2] d. Maltose consists of bonded to .

[2] e. The active ingredient in tobacco is . It belongs to the class of chemicals called .

[2] g. In terms of chemical reactions, the most important difference between an amine nitrogen and an amide nitrogen is

2. Draw one clear structural formula for each of the following:

a. [6] a Fisher projection of chiral secondary amine which has the formula C3H9ON	b. [5] a Haworth projection of beta-D-galactose
c. [5] a Fisher projection of a meso compound with the formula C4H10O4	d. [4] D-glyceraldehyde

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4. Draw the structures of the major organic products of the following reactions.

a. [6]

b. [6]

5. [6] Is it possible for the two compounds below to hydrogen bond to each other. If "yes", draw a simple labeled sketch of the bonding. If "no", explain why not.

6. An organic compound X is not soluble in water. It dissolves in basic solutions such as NaOH(aq). The original compound precipitates out of solution when it is made acidic with hydrochloric acid. See the diagram below.

a. [4] In what family of compounds does X belong? .

b. [5] Briefly explain why you chose this answer.

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7. [8] Name the following compound.

8. [3] What is a non-reducing sugar?

[2] Name one:

[5] Draw the chemical structure of any non-reducing sugar, not necessarily the one you named.

9. [5] a. In the following compound circle and label all of the acidic sites and all of the basic sites.

c. [5] Draw carefully placed arrows to each and every atom in the compound that can hydrogen bond to water.

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10. [6] Honey is an aqueous solution containing a mixture of glucose and fructose. Describe the similarities and differences between the sugar in honey and ordinary table sugar (sucrose) in terms of a. their chemical structures and b. consequences for digestion.

11. a. [4] Briefly describe the difference between amylose & amylopectin. b. [4] Draw a simple sketch.

c. [4] Would you expect there to be a substantial difference in the amount of energy (calories) that these two forms of starch would yield when eaten and completely digested? Explain. [=12]

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