Explanation of Behavior

Compounds such as naphthalene and 1,4-dichlorobenzene find use as mothballs since they sublime at a slow rate at atmospheric pressure. Explain this behavior in terms of the structure of the molecules.

Caffeine

(A) How many peaks would you expect to find in the NMR spectrum of caffeine? (B) What characteristic absorption bands would you expect to find in the infrared spectrum of caffeine?

Solid-Vapor Equilibrium

To color spots on TLC plates for easier visualization after elution with solvent, the plates can be "developed" in a sealed chamber containing solid iodine. Explain how the solid-vapor equilibrium operates in this instance.

Ethyl Acetate as an Elution Solvent

Caffeine is soluble in ethyl acetate. Do you think that the purity of your product could be checked by TLC using ethyl acetate as an elution solvent? Explain.

Preparation of Esters in an Experiment

Consider the following reaction: Lauric acid + Ethanol yields Ethyl laurate + Acetic acid In the preparation of the esters given in this reaction, the reaction product is extracted with 5% sodium bicarbonate solution (NaHCO3)in the isolation step. Why? What gas is evolved during this washing step? Write a balanced equation for the reaction that produced it.