Editing Notes On Chemical And Physical Change

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<center>Notes on Chemical and Physical Change</center> 
 
Physical Change 
#[[Particles]] do not change, just changing spacing or other parameters of the [[Particles]]
#occurs when one or more physical properties of a substance are changed but without any change in the substance's chemical properties or composition
#no new substance is formed
#all changes of phase are physical changes (from solid to liquid to gas)

Chemical Change 
#[[Particles]] does change and creates a new set or set(s) of particles (grouping of atoms). Usually this is accomplished by valence electrons being shared or transferred between atoms differently than before. 
#is any change that results in the production of one or more substances that differ in chemical properties and composition from the original substances
#examples are the rusting of iron, the souring of milk, the burning of paper

Changes in Energy 
#every change, either physical or chemical, involves an energy change
#generally the energy changes that accompany physical changes are not as noticeable as those that accompany chemical changes
#energy can be ''released'' (exothermic) or ''consumed'' (endothermic) during the reaction

IMPORTANT: Lavoisier's principle of the '''Law of Conservation of Mass''' states that "matter ''cannot'' be created or destroyed by a chemical change."

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