Transcript Chemistry 21 power point

Chemistry
Physical Properties
• I can describe this car by:
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Red and black
Smooth texture
Mass of 28 g
Wheels are circular
89 cm3
Physical Properties
• The characteristics of
a substance that can
be observed without
changing the identity
of the substance.
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Color
Shape
Size
Texture
Volume
Mass
Density
Let’s Review Density
• If animal has a mass
of 75 grams and has
a volume of 25 cm3.
What is animal’s
density?
• 75g/25cm3 = 3
g/cm3.
Physical Properties
Physical Change
• A physical change is a change in a substance
that does not change the substance into a
different one.
Physical Change
How do I make a physical change?
Chemical Properties
• Describe how substances can form new
substances.
– Ability for wood to burn
– Ability for metal to rust
– Ability for material to explode
Chemical Changes
• The change of one
substance into
another substance.
– Production of odor
– Change in
temperature
– Change in color
– Formation of bubbles
– Formation of a solid
How can I make the wood have a chemical change?
What can be done with the pizza to have a chemical
change?
How can you tell a chemical change has taken
place?
Is it Physical or Chemical?
Is it physical or chemical?
Is it physical or chemical?