Water Floats on Oil
Oil
floats on water, that much we know, right?
Well, physicists are about to turn your world upside down (again): under
certain conditions, water can actually float on oil.
Using a theoretical model, the scientists calculated the forces
acting on water when it is dripped onto an oil surface. Taking into
account surface tension, the property that allows some insects to walk
on water, they showed that a water droplet can "hang" from
the oil’s surface. The oil surface droops like a rubber membrane, allowing
the above air—which is much lighter than oil and water—to
extend beneath the surface’s average level. With help from the surface
tension, this air pocket balances the weight of the water droplet, preventing
it from sinking. The scientists confirmed the model’s predictions in
tests and found that water droplets up to 170 microliters in volume
could float on oil
Link
| The published study on Langmuir,
if you’re so inclined
Previously on Neatorama: 5
Really Weird Things About Water
