What new inforamtion can you add the your definition of physical change?

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A physical change is one in which a substance may change its form but still retain it's original chemical composition. An example of a physical change is a phase change where a substance changes from one phase (solid, liquid, gas) to another.

Using water as an example: As water changes from water vapor to liquid and freezes to ice, the chemical formula remains the same; H2O.