Question

7) As you are cleaning out the shared refrigerator in the kitchen of your apartment at the end of the school year, container in the back, left there by one of your roommates. This container is half-filled with something that you notice has separated into two layers: the top one is a dark yellow color, the bottom layer is more greenish. You assume that this biphasic mixture has an aqueous layer and some type of organic layer. Without tasting, smelling, or removing either layer from the container, how can you determine which layer is the aqueous layer using just material found in a typical kitchen? 2 points

Answer 1

With the help of table spoon, slowly add some cooking oil to the container and observe what happens. Cooking oil is immiscible with aqueous layer. However cooking oil is miscible with organic layer. If the top layer is aqueous layer, then in the top layer, you will see the droplets of cooking oil dispersed in top layer. If the top layer is organic layer, then in the top layer, you will NOT see the droplets of cooking oil dispersed in top layer.