Science, Periodic Table

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