Question

HELP!! write down the chemical equations that allow the separation of a mixture of biphenyl and N, N-diethylaniline, a liquid that is a base and not an acid

Answer 1

We can separate aniline from the mixture of biphenyl and N,N-diethylaniline by addition of dilute HCl to the mixture. As N,N-diethylaniline is a base it will get dissolved in the dilute acid by forming salt. Then we can separate the aqueous layer.

Note that addition of dilute acid will form a aqueous layer because biphenyl is not miscible with water. Only N,N-diethylaniline will be dissolved into the aqueous layer and the biphenyl will remain in the organic layer.

Then we take the aqueous layer in which the salt of N,N-diethylaniline is present and treat it with NaOH to get pure N,N-diethylaniline.

Equation:

Reaction with dilute HCl to form salt:

Reaction of salt with NaOH to get pure N,N-diethylaniline:

Now, we have pure biphenyl in the organic layer and N,N-diethylaniline is separated from aqueous layer.