PHYSICAL CHANGE:
A change that does not involve the formation of new substances.
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Physical changes are not represented by equations because they do not involve the rearrangement of atoms. Since no new substances are formed, this means that the atoms of the substance are not broken, changed, or rearranged. Unlike chemical changes, physical changes involve a change in the state of matter. For example, the crushing of a soda can. The physical appearance of the object itself changed, but no new substances were created and there weren't any changes to that object's molecular structure, therefore, those changes cannot be represented by equations.
Hope that helps and good luck!
