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Physical Changes |
Physical changes begin and end with the same type of matter. Physical changes can be changes in size or shape, change in position or texture, and a change in state. The type of matter and properties do not change. Examples are an ice cube melting, cutting paper into different shapes or raking leaves. Water does not change its properties even if it is melted, frozen, or heated. Books and furniture cannot change state regardless of the amount of heat added to it.
Water can exist in more than one state. Water can exist as a solid, liquid, and gas. Taking away heat or losing heat causes matter to change from one state to another. For solids, when heat is added to it, the particles vibrate more rapidly, and cause the solid to change to a liquid. For liquids, adding more heat will cause the particles to move fast so that they break away from one another. Some particles may escape as gas. For gas, particles move fast and adding heat makes them move farther and faster apart. An example is pond water that evaporates faster in summer because of the higher air temperature which adds heat energy to the surface water. This causes the particles to move farther apart and escape as gas.
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