The solvent diethyl ether can be mixed with water but only by shaking the two liquids together. After the shaking is stopped, the liquids separate into two layers, much like oil and vinegar. The free-base form of the alkaloid caffeine is readily soluble in diethyl ether but not in water. Suggest what might happen to the caffeine of a caffeinated beverage if the beverage was first made alkaline with sodium hydroxide and then shaken with some diethyl ether.
A. The water layer would turn a pink color indicating an alkaline pH.
B. The caffeine would transform into the free acid and transfer into the diethyl ether.
C. The caffeine would transform into the free base and transfer into the diethyl ether.
D. The diethyl ether and water would mix into one layer.
Answer: C
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