Question

A student is performing an acid-base extraction on unknown compounds, and she extracts the organic layer with 5% HCl solution and separates off the aqueous layer. She then adds sodium hydroxide solution to the aqueous layer and observes a white precipitate. Which of the following functional group(s) is most likely in the precipitated compound?
a. ether
b. amine
c. carboxylic acid
d. ester

Answer 1

Answer:

amine

Explanation:

We have to bear in mind that amines are basic compounds. This idea will be very important in attempting to answer this question.

So, when she adds 5% HCl solution in order to extract the organic layer, the amine forms a hydrochloride salt which is contained in the aqueous layer.

The addition of a base such as NaOH leads to the formation of a white precipitate of the amine.