If oil floats on water, why is it that when we wash our hands the oil doesn’t get displaced by the water but sticks to our hands instead?

Question

If oil floats on water, why is it that when we wash our hands the oil doesn’t get displaced by the water but sticks to our hands instead?

In: 20

Answer 1

There are forces at play besides buoyancy. The attractive force between liquids and solids is stronger than buoyancy when there’s a small amount of liquid, and so oils stay stuck to your hand.