Physical/Chemical Changes

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Physical/Chemical Changes
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Physical Properties

• Any property of matter that can be measured
  without changing its chemical nature is known as
  a PHYSICAL PROPERTY!
• What are some of your
• PHYSICAL PROPERTIES?

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PHYSICAL PROPERTIES OF MATTER

• Color
• Texture
• Melting Point
• Boiling Point
• Mass
• Volume
• Density

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PHYSICAL CHANGES

• Matter can undergo PHYSICAL CHANGES!
• A PHYSICAL CHANGES only affects PHYSICAL
  PROPERTIES, chemical properties are NOT affected.
• PHYSICAL CHANGES involve changes in ENERGY!

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EXAMPLES OF PHYSICAL CHANGES

• ONLY THE PHYSICAL SUBSTANCE CHANGES!
• Melting
• Boiling
• Freezing
• Condensation

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CHEMICAL PROPERTIES

• Matter cannot be fully described by physical
  properties alone! We need to also look at how
  matter interacts with other types of matter.
• To describe this type of behavior, CHEMICAL
  PROPERTIES must be considered.

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CHEMICAL PROPERTIES

• CHEMICAL PROPERTIESa property of matter that can
  be observed only when substances interact with
  one another.
• CHEMICAL CHANGESa change that produces one or
  more new substances.
• (The reactions we were talking about yesterday!)

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CHEMICAL CHANGES

• All CHEMICAL CHANGES deal with changes in energy!
  Therefore, all CHEMICAL CHANGES can be
  classified as either ENDOTHERMIC or EXOTHERMIC.
  (p. 19)

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EXAMPLES OF CHEMICAL CHANGES

1. Evolution of a gas
2. Formation of a precipitate
3. Evolution or absorption of heat
4. Emission of light
5. Color change in reaction system