Paleontologists distinguish rocks from dinosaur bones by tou

Paleontologists distinguish rocks from dinosaur bones by touching their tongues to the object. If their tongue sticks, it is considered bone. This occurs because the water from the tongue moves up the porous spaces of bone. What property of water is allowing this to occur?

Solution

This experiment is based on capillary action of water.

Capillary action: It is a property of a liquid to flow in narrow spaces without assistance of external forces like gravity or we can say, opposite to the gravity. Capillary action of water occurs because of intermolecular forces between water molecules and the surrounding solid surface. In this phenomena adhesive forces play their role. When adhesive forces between water molecules and the solid surface are stronger than the cohesive forces between water molecules then water show their capillary action property.

In the above experiment, structure of bones are porous in nature when Paleontologists touch the bones with their tongue water moves from their tongue to pores of the bones due to water capillary action (driving force is adhesive forces between water molecules and the solid surface of the pores of the bones) and he felt some dryness on their tongue.