Water can exist as individual molecules, suspended in air, in constant collision with other molecules. In this state, water is termed gas. Water also exists as a liquid where the molecules are stuck or bonded together. As the attraction between these molecules increases, water can become a solid, and the molecules establish a complex symmetrical orientation (like a snowflake!) The question is: how do molecules of water (or any substance) stick together to form liquids and solids? What are the fo