Physical Changes

• Changes in matter that do not alter the identity of the matter itself.
• For example:
1. Size
2. Shape
3. State - solid  liquid  gas
4. Dilutions

 
Chemical Changes
1. Changes that do alter the identity of a substance.
2. For example:
1. Iron rusting
4 Fe(s) + 3 O_2(g) 2 Fe₂O₃ • 3 H₂O
1. Wood burning
2. Copper turning to brass

 
Common Errors
• Ice melting, water freezing, water evaporating, and steam condensing are all examples of a state change.
• These are physical changes, not chemical.
• Diluting a solution is a physical change, even if the color becomes more faint.