How does the nonpolar character of oil molecules helps when removing oil from water using nets and floating barriers?
Have you never used a separating funnel?
The less dense (typically organic) phase lies atop an aqueous phase in which it is immiscible. The long chain oil molecules, whose principle intermolecular attraction is the dispersion force, cannot be effectively solvated by water.
Crude oil is typically slightly less dense than water, and it should float on water in the event of an oil spill.
Just as an aside, I once had a