Why does an artificial sponge absorb more water than a natural sponge?
Water is drawn into a sponge in part because of an attraction between the water molecules and the sponge’s surface and in part because of water’s tendency to minimize its own surface area. When you put a drop of water on a waxy surface, the water beads up. That’s because water and wax don’t bind well to one another and the water molecules pull toward one another instead. The water droplet tries as best it can for form a sphere, since a sphere has the smallest surface area that a given volume of water can occupy. These forces that pull water’s surface inward are called surface tension. But when you put a drop of water on real cellophane (a smooth form of cellulose), the water spreads out. That’s because water and cellulose bind strongly to one another and the water will permit its surface area to increase somewhat if that increase allows it to attach to more cellulose. Similarly, water binds well with other forms of cellulose, including paper, cotton, and Rayon. I think that most artifi
