Physical or Chemical ?

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Physical or Chemical ?

• Number your paper 1 22
• As you watch the slideshow write a PC if you
  think a physical change is happening.
• Write CC if you think a chemical change is
  happening.

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• REMEMBER
• When a physical change happens only a physical
  property such as size, shape, or state has
  changed, but the identity of the substance is
  still the same.
• When a chemical change takes place new substances
  are formed and the clues this has happened are
  fizzing, changing color, changing odor, heat,
  light or sound.

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Photosynthesis
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Making a metal sculpture
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Leaves changing in the Fall
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A lake freezing
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Digesting food
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Baking bread
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Dissolving sugar
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• Now lets see how well you did!

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1.CHEMICAL CHANGE Sodium - bicarbonate tablets or
alka- seltzer react with water to make a new
product.
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2. CHEMICAL CHANGE
Wood is turned into smoke and ash as it reacts to
extreme heat.
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3. PHYSICAL CHANGE
Crushing a can changes the shape of the can but
not its chemical make up.
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4. CHEMICAL CHANGE When an egg fries it reacts to
heat and the change cannot be reversed.
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5. CHEMICAL CHANGE
Fireworks are what happens when gunpowder reacts
to heat.
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6. PHYSICAL CHANGE Water freezing is a change in
state.
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7. PHYSICAL CHANGE Ice
cream melting is also a change in
state, which is a physical change.
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8. PHYSICAL CHANGE
Tearing paper creates smaller pieces but it is
still paper.
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9. CHEMICAL CHANGE Photosynthesis is when plants
react to sunlight creating energy and oxygen.
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10. PHYSICAL CHANGE Play dough can be molded into
different shapes but it is still has the same
make up.
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11. PHYSICAL CHANGE Like Play dough, clay can
also be molded but it is still has the same make
up.
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12. CHEMICAL CHANGE The rust on this pulley is
what is created when iron reacts with oxygen.
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13. PHYSICAL CHANGE
Cutting cloth creates smaller pieces but NOT a
new substance.
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14. PHYSICAL CHANGE This metal sculpture
shows the malleability of copper.
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15. CHEMICAL CHANGE Leaves change in the fall as
the plant reacts to light and temperature
changes.
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16. CHEMICAL CHANGE As a match tip strikes a
surface it reacts to the heat from the friction.
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17. PHYSICAL CHANGE Glass is still glass, even
when it breaks into pieces.
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18. PHYSICAL CHANGE This lake freezing over is a
change in state.
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19. CHEMICAL CHANGE When we eat, our food
reacts with acid in our stomach to help create
energy.
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20. CHEMICAL CHANGE The flour, water, salt
have reacted to heat and made bread.
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21. PHYSICAL CHANGE Both the sugar and the water
can be easily separated have retained their
chemical properties.
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22. CHEMICAL CHANGE
The sugar in the marshmallow reacted with the
heat caramelizing it.