Physical and Chemical Changes

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Physical and Chemical Changes

• A Write On Activity

Free powerpoints at http//www.worldofteaching.com
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Objective Chemical/Physical Change
Differentiate

• The learner will be able to distinguish between a
  physical and chemical change.

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Matter

• Matter is everywhere.
• Matter is anything that takes up space and has
  mass.
• Matter is constantly experiencing both chemical
  and physical changes.

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The difference between Physical Property and
Physical change.

• The physical property is the materials ability
  to change what it looks like but not change what
  it is
• The physical change is the actual process of
  changing shapes.

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Physical Change vs. Property

• Physical changes occur when matter changes its
  property but not its chemical nature.
• Physical property changes could include a change
  in texture, shape, size, color, odor, volume,
  mass, weight, and density.

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Examples of physical changes

• Crushing an aluminum can
• Melting
• Dissolving sugar in water
• Bending a paper clip
• Freezing water for ice cubes
• Mixing oil and vinegar
• Cutting your hair
• Sanding a piece of wood

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Physical Change
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Chemical Change

• Chemical changes are changes matter undergoes
  when it becomes new or different matter.
• To identify a chemical change look for signs such
  as color change, bubbling and fizzing, light
  production, smoke, and presence of heat.

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Chemical Change

• A chemical change occurs when fireworks are used.
  Fireworks are made of metals such as magnesium
  and copper. These change chemically as they
  light up the sky.

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Examples of Chemical changes

• Soured milk
• Alka seltzer
• Statue of liberty being eroded by acid rain
• Space shuttle launch

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Chemistry Matter

• We can explore the MACROSCOPIC world what we
  can see
• to understand the PARTICULATE worlds we cannot
  see.
• We write SYMBOLS to describe these worlds.

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Kinetic Nature of Matter

• Matter consists of atoms and molecules in MOTION.

Dense/Slow
Less Dense/Faster
Least Dense/Fastest
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The In-Betweenies Physical or chemical?

• Some properties (abilities) can be either
  physical or chemical
• Examples
• Ability to change color
• Ability to make a gas

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Both of these examples are making a gas. Which
one is physical and which is chemical?
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Both of these pictures show a color change due to
heat which is physical and which is chemical?
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1. Is it a chemical or physical change?

• Sugar dissolving in tea

• Chemical Change

• Physical Change

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OOPS!

• Did it change size, color, shape (Physical
  Change)?
• or
• Did it become different matter (Chemical Change)?

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Correct!
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2. Is it a chemical or physical change?

• Logs burning

• Chemical Change

• Physical Change

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OOPS!

• Did it change size, color, shape (Physical
  Change)?
• or
• Did it become different matter (Chemical Change)?

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Correct!
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3.Is it a chemical or physical change?

• Melting an ice cube to become water.

• Chemical Change

• Physical Change

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OOPS!

• Did it change size, color, shape (Physical
  Change)?
• or
• Did it become different matter (Chemical Change)?

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Correct!
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4.Is it a chemical or physical change?

• Cutting paper

• Chemical Change

• Physical Change

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OOPS!

• Did it change size, color, shape (Physical
  Change)?
• or
• Did it become different matter (Chemical Change)?

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Correct!
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5.Is it a chemical or physical change?

• Crushing an aspirin

• Chemical Change

• Physical Change

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OOPS!

• Did it change size, color, shape (Physical
  Change)?
• or
• Did it become different matter (Chemical Change)?

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Correct!
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6. Is it a chemical or physical change?

• Metal rusting

• Chemical Change

• Physical Change

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OOPS!

• Did it change size, color, shape (Physical
  Change)?
• or
• Did it become different matter (Chemical Change)?

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Correct!
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7.Is it a chemical or physical change?

• Lighter fluid burning

• Chemical Change

• Physical Change

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OOPS!

• Did it change size, color, shape (Physical
  Change)?
• or
• Did it become different matter (Chemical Change)?

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Correct!
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8.Is it a chemical or physical change?

• An egg rotting

• Chemical Change

• Physical Change

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OOPS!

• Did it change size, color, shape (Physical
  Change)?
• or
• Did it become different matter (Chemical Change)?

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Correct!
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9. Is it a chemical or physical change?

• An egg breaking

• Chemical Change

• Physical Change

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OOPS!

• Did it change size, color, shape (Physical
  Change)?
• or
• Did it become different matter (Chemical Change)?

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Correct!
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Writing Activity

• Write a paragraph about the difference between a
  chemical and physical change. Give examples of
  each.