Sample pre-lab quiz for the Sulfanilamide experiment.

1) The discovery of sulfa drugs is credited to Paul Ehrlich. He first looked at compounds that were _____ because they had an affinity for (stained) _____. This led to the discovery of sulfa drugs, which are _______ .

1. dyes, fungus, anti-fungal
2. aromatic, bacteria, anti-yeast
3. crystals, lichen, ineffective
4. dyes, bacteria, anti-bacterial

2) (1 pt) What is the compound (?) that belongs above the arrow compound in the following reaction:

1. chlorosulfonic acid, HSO₃Cl
2. sulfuric acid, H₂SO₄
3. hydrochloric acid (HCl) and H₂SO₄
4. sodium hydroxide, NaOH

3) The first step of this reaction is:

1. acetanilide is poured into a flask, cooled, and chlorosulfonic acid is added
2. acetanilide, a solid, is placed in a flask and heated with a flame until it melts, then allowed to solidify before chlorosulfonic acid is added
3. acetanilide and chlorosulfonic acid are refluxed until the mixture becomes brownish orange
4. acetanilide and chlorosulfonic acid are shaken together in a separatory funnel

4) In one step of this experiment, a compound similar to the one below is prepared. As drawn, this compound is soluble in aqueous solution. What should you do to cause this compound to crash out of solution (i.e., to become insoluble in water)?

1. increase the pH
2. put it on ice
3. decrease the pH
4. boil off all the solvent

5) What compound in the sulfanilamide experiment is the most hazardous to your immediate health and welfare?

1. chlorosulfonic acid
2. acetanilide
3. ammonium hydroxide
4. sulfanilamide

6) In the sulfanilamide experiment, acetanilide is the limiting reagent. If you begin with 1.0 g of acetanilide, what is the theoretical yield?

1. (1/172) x 135
2. 1 x 1.21
3. (1/135) x 172
4. 1.0 g

Answers.