Question

As you are cleaning out the shared refrigerator in the kitchen of your apartment at the end of the school year, you find an unlabeled, clear plastic 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 other type of 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?

Answer 1

Table salt (Sodium chloride) can be found in a typical kitchen. This is an ionic compound and soluble in only polar, high dielectric constant solvents like water. If you can take small amount of upper dark yellow layer one into a tablespoon and try to dissolve small crystal of table salt in it. If salt dissolved in that layer this confirms that dark yellow layer is aqueous layer otherwise it will be organic layer.

Thank You So Much! Please Rate this answer as you wish.