Physical & Chemical Changes
Transcript of Physical & Chemical Changes
Physical & Chemical Changes
•Is melted butter still butter?•Is soured milk still milk?•Are the ashes from a fire made of the same “stuff” as wood?
7th Grade
Brandy Butcher
What is a physical change?
Change that affects one or more physical properties of a substance
A new substance is not formed
The substance keeps its identity (name)
Examples of Physical ChangeAny state change
◦Melting◦Freezing◦Evaporating
DissolvingCuttingBending
Examples of Physical Changes in NatureWater Cycle
Erosion
Can you think of any examples?
What is a chemical change?One or more substances are
changed into a new substance
New and different properties
New identity (name)
Examples of a Chemical Change
Cooking Burning
Rusting
Examples of Chemical Changes in NatureCarbon Cycle
Nitrogen Cycle
Chemical Weathering
Can you think of any examples?
What are the signs a chemical change is happening?Change in colorChange in odorProduction of heatProduction of fizzing, foam,
bubblesProduction of soundProduction of light
What signs do this changes demonstrate?
Light/Sound/
Heat
Light/Sound/
Heat
Change in odor and color
Change in color
Change in odor and color
Physical or Chemical Change?
Frying an egg?
Physical or Chemical
Incorrect. Try again!
Correct!
Try the next one!
Physical or Chemical Change?
Souring Milk?
Physical or Chemical
Incorrect. Try again!
Correct!
Try the next one!
Physical or Chemical Change?
Shredding paper?
Physical or Chemical
Incorrect. Try again!
Correct!
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