Physical or Chemical
Properties/Changes
Elkins 2015-2016
Physical or Chemical
• Matter can change in two ways – physical or
chemical.
Physical Change
• With a physical change no new substance is
created and the original matter can be
recovered. Physical change does not change
the composition of the matter. The original
matter is still present. The substance may
seem different, but the way the atoms are
linked up are the same.
Physical Change
Physical changes include:
• Changing the shape or size
• Dissolving
• Changing from one state of matter to
another
Matter
Matter can change from one state to another
by increasing or decreasing temperature or
pressure.
Examples of Physical Change
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water evaporating or water changing to steam
clothes drying in a dryer
chopping wood - wood ground to sawdust
erosion
rock breaking
mixing Kool-Aid
Physical Properties
Physical Properties
Physical Properties describe objects (matter)
and are used to identify and compare
different types of matter
Color, odor, size, shape, state (phase), texture,
hardness, taste, density, boiling point, melting
point, freezing point, magnetism, conductivity,
conducts heat, mass, weight, volume,
solubility …
Chemical Change
• When a chemical change takes place, a new
substance is made. The old matter is no longer
present. The matter can not be changed back
into its original state. The way the molecules
are linked up is different when a chemical
change takes place.
Signs of Chemical Change
• gas bubbles
• color change - leaves turning colors in the fall,
rust appearing
• disappearance of color – fading fabric
• heat or light
• forms a precipitate
Examples of Chemical Changes
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fruit rotting, food spoiling
rust
decay of plants
burning wood
silver tarnishing
car burning gas
baking bread
Is this a physical or chemical change?
dirt added to a puddle of water