Change in Physical State. Heat also affects how molecules interact with each other. Heating a solid above a certain temperature will cause it to melt to form a liquid; further heating causes this liquid to boil to form a vapor.
When water is in its solid state (ice) , the water molecules are packed close together preventing it from changing shape. Ice has a very regular pattern with the molecules rigidly apart from one another connected by the hydrogen bonds that form a crystalline lattice.
1 Freezing is the process that causes a substance to change from a liquid to a solid. 2  Freezing occurs when the molecules of a liquid slow down enough that their attractions cause them to arrange themselves into fixed positions as a solid.ome small drops of water may appear higher on the can where it is not as cold. Describe what happens to water molecules as they move from being water vapor near the can to ice on the can. Water vapor molecules in the air near the can cooled when energy from the air transferred to the cold can.