you have unknows that are carboxylic acid, an ester, and amine. Describe how you would distinguish among them.

Question

You can have these three unknows in Lab and if you are asked to distinguish them how would you know?

Answer 1

The simplest way is to dissolve a small amount in water.
Then use a pH indicator: the acid has pH<7, the ester pH=7 and the amine pH>7

If none of them is much soluble in water to start with, then try dissolving them in dilute NaOH and in dilute HCl.
The ester that doesn't dissolve in water will not dissolve neither in acid nor in base.
A carboxylic acid which cannot dissolve in water will not dissolve in acid but will dissolve in base because the soluble salt will be formed.
Similarly an amine that doesn't dissolve in water, will not dissolve in base but will dissolve in acid due to the formation of the soluble salt.

Answer 2

An ester is a candy-smelling substance The carboxylic acid has the comparable residences as standard acids i.e they turn blue litmis crimson, habit electrical energy while in answer Amine acts as a base, so will turn crimson litmis blue and so on

Answer 3

Depends on what I have available.

I'd just use an FTIR spectra. You didn't say what type of lab (wet or instrumental).

Answer 4

I asked this same question many times, and didn't get a good answer

Answer 5

boiling points, melting points, and the aforementioned IR spectra