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Science, Periodic Table
changes like melting and freezing that can be undone
changes that last forever like rusting metal
a change that only happens in appearance, the molecules have not changed, a physical change can be weathering
a change that molecules break-up and reform,it is not reversible, physical properties change but not molecules
change including, shape, size, texture, volume, mass, weight or density
number of protons
Atomic Mass - Atomic Number =
Number of Neutrons