2. Physical Change  Physical change is a change that occurs that does not change the identity of the substance  A change in which matter looks different but is still the same matter.  A change that affects the size, shape or color of a substance but does not affect its composition

3. E XAMPLES OF PHYSICAL CHANGES Cutting paper Mashing potatoes Painting a wall Breaking glass Melting marshmallows Molding clay Water freezing Water boiling Thawing meat

4.  A physical change alters the form of a substance, but does not change it to another substance. Making Orange Juice

5.  Chemical change is a change that occurs causing the identity of the substance to change. Examples include: >Burning wood >Digesting food >Potassium reacting with water A chemical change can also be called a chemical reaction.

6. Wood burning to ash and smoke (a new substance is formed) Iron rusting Marshmallows burning Apple rotting Toasting bread Examples of Chemical ChangesChemical Changes

7. . Example: Baking a Cake

8. Indicators of a Chemical Change Indicators of a chemical change can include:  Light is produced  Heat is either absorbed or produced  Gas is produced  There is a change in color  Formation of a precipitate

9. Differences between physical and chemical changes  With a physical change, the item can be change back to its original form  With a chemical change, the item cannot be changed back to its original form

10. I S IT A C HEMICAL OR A P HYSICAL C HANGE Type of ChangePhysicalChemical Melting ice Burning wood Souring milk Wadding up paper Rusting metal Corn Starch and Water Corn Plastic Adapted from: www.dpi.state.nc.us/docs/curriculum/science/units/.../8unit2pt2. ppt

11. Thank you