2. Consider the following solvent pairs. If mixed together, which pairs would form two layers? If they form two layers, which solvent would be on top? Find the densities for each of these solvents in the CRC Handbook. [6 mks]

a. hexanes and water
b. water and methylene chloride
c. hexanes and methylene chloride
d. methanol and hexanes
e. ethanol and water
f. acetone and toluene

1 answer

Did you look up the densities? The one with the lowest density will float on top. But note that e is miscible in all proportions and you won't have two layers. Same for f. So you have two questions here. First is which pairs will NOT mix. Of those, the lower density will float.