Question

How do we assess the relative densities of liquids. Will oil float on water?

Answer 1

Well does oil float on water? What does this suggest about the relative densities..........?

Explanation:

Most organic solvents that are immiscible with water, float above the above the water layer when you do a phase extraction with a separating funnel. And this reasonably suggests that the aqueous phase IS MORE DENSE than the organic phase.

One exception is `"methylene chloride"`, which has `rho=1.33*g*cm^-3`. But this is an exceptional case. Most organic solvents, `"petroleum ether"`, `Et_2O`, are LESS DENSE than water and will float ABOVE the aqueous phase.