Physical and Chemical Changes Physical Change Physical change

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Physical and Chemical Changes

Physical and Chemical Changes

Physical Change Physical change is a change that occurs that does not change the

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

EXAMPLES OF PHYSICAL CHANGES • • • Cutting paper Mashing potatoes Painting a wall

EXAMPLES OF PHYSICAL CHANGES • • • Cutting paper Mashing potatoes Painting a wall Breaking glass Melting marshmallows Molding clay Water freezing Water boiling Thawing meat

 A physical change alters the form of a substance, but does not change

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

Chemical Change Chemical change is a change that occurs causing the identity of the

Chemical Change 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. Ø

Examples of Chemical Changes Wood burning to ash and smoke (a new substance is

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

. When a substance undergoes a chemical change, it is changed into a different

. When a substance undergoes a chemical change, it is changed into a different substance with different properties Example: Baking a Cake

Indicators of a Chemical Change Indicators of a chemical change can include: v. Light

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

Differences between physical and chemical changes With a physical change, the item can be

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

IS IT A CHEMICAL OR A PHYSICAL CHANGE Type of Change Physical Chemical Melting

IS IT A CHEMICAL OR A PHYSICAL CHANGE Type of Change Physical Chemical 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/. . . /8 unit 2 pt 2. ppt

 Thank you

Thank you