Question

A cotton ball soaked in an unknown amine
and another one soaked in an acid were
placed at opposite ends of a 1.00 m glass
tube (see the diagram). In one combina-
tion of acid and amine, a white ring was
observed almost exactly halfway be-
tween the two ends. Which acid and
which amine were used? [Me = methyl,
Ac = acetyl]
​

Answer 1

Answer:

The ammonia gas, having a lower molecular weight than the hydrogen chloride, will diffuse faster and travel a greater length of the tube. Consequently, the white ring of ammonium chloride will form much closer to hydrochloric acid end of the tube.