If the bottom layer contains the solute, follow these steps after draining the bottom layer:

1. Rather than draining the top layer through the stopcock, pour this layer out through the mouth of the funnel into a beaker or flask.

2. Video: Pour out the top phase ( 1.75 M )

3. Pour the bottom layer back into the separatory funnel.
4. Extract the bottom layer solution two more times, following the same procedure as for the first extraction.
5. Combine the bottom layers.
6. Discard the top layers, but be certain that the solute was in the bottom layers before disposing of any solutions.