5. Why do paintballs swell when dropped in

water?

Through osmosis, water will pass through the gelatin membrane and hydrogen bond with the polyethylene glycol within. Since the concentration of water is much greater outside of the paintball than inside, water will diffuse inward in an attempt to equalize the con - centration of water.

If a paintball is dropped into a beaker of water, it will expand to an impressive size. Through osmosis, water will pass through the gelatin membrane and hydrogen bond with the polyethylene glycol within. Since the concentration of water is much greater outside of the paintball than inside, water will diffuse inward in an attempt to equalize the concentration of water. Water will continue to travel through the gelatin membrane until the concentration of water inside the paintball is equal to the concentration of the water on the outside of the paintball. However, as it swells the gelatin shell will break down, spilling the contents before equilibrium is reached.