posted by Scarlet .
5. Look up the density of n-butyl chloride (1-chlorobutane). Assume that this alkyl halide was prepared instead of the bromide. Decide whether the alkyl chloride would appear as the upper or lower phase at each stage of the separation procedure: after the reflux, after the addition of water, and after the addition of sodium bicarbonate.
So what is your problem? Have you looked up the densities? The more dense will sink in the water layer; the less dense will float in the water layer.