Magic Sand Video

Wow, what an amazing phenomena! It is uncommon in our daily life, right? It is observed that when the grains of blue solid are poured into water, the air bubble separates it from the water and makes it appear silvery and does not become wet. It can be molded into structures that hold their shape under water. When the water is decanted, the grains are completely dry and not clump together (i.e. free flowing).

The reason behind it is because the magic sand weight is not large enough to break the surface tension of water. The surface tension is an internal pressure caused by the attraction of molecules below the surface for those at the surface of water. This molecular attraction creates an inward pull, or internal pressure, which tends to restrict the tendency of the liquid to flow and form a large interface with another substance. However, once an additional force (pressing by glass rod) is applied, the grains can overcome the surface tension and sinks into the bottom of the glass.