Physical and Chemical changes

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Physical and Chemical changes Chapter ALL over
the book
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Physical Changes
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1) Physical changes affect the physical
properties of matter (things like size, shape,
appearance) -ripping paper would be a physical
change -other examples changes of state,
dissolving, crushing Many physical changes can
be undone
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2) ALL changes of state are physical changes A
change of state is the change of a substance
from one physical form to another
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• 3) During a change of state, the energy of a
  substance changes, and particles speed up or slow
  down.
• If energy is added to particles they go faster
• b) If energy is removed, particles move slower.

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4) Melting change from a solid to a liquid. a)
The temperature at which a substance will melt is
called the melting point.
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5) When a solid absorbs more energy the
particles will move faster and as they overcome
their attraction to each other they transform
into a liquid.
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• 6) Freezing change from a liquid to a solid.
• The temperature at which a substance will freeze
  is called its freezing point.
• b) The melting point and freezing point of a
  substance are the same temperature.

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7) When liquids cool, they lose energy and the
particles slow down and their attraction
overcomes motion, and they become locked together
to form a solid.
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• 8) Vaporization change from a liquid to a gas.
• there are two types -boiling and evaporation
• boiling liquid becomes gas throughout the
  liquid
• evaporation liquid becomes
• gas only on the surface of the
• liquid

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9) Condensation change from gas to liquid a-
energy is removed, and particles slow down b-
condensation point temperature at which gas
will become liquid
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10) Sublimation change from a solid directly to
a gas
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Chemical Changes
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12) Chemical changes one or more substances are
changed into an entirely new substance with
different properties.
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13) Clues to chemical change a) color
changes b) fizzing or foaming c) heat
changes d) production of sound, light, color
14) Chemical changes cannot be undone using
normal physical processes.
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15) In a chemical change, the items that combine
together are called reactants, the resulting
substance is called a product
Reactants . . . . . . . . . . . . . . . . . . . .
. . . Products
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Which type of change? Which type of change?
ACTION TAKING PLACE PHYSICAL OR CHEMICAL CHANGE.
Glass breaking  
Ice cube melting  
Candle burning  
Food digested in your stomach  
Glass breaking  
Marshmallow burning  
Lake freezing  
Bread baking  
Sugar dissolving  
Popsicle melting  
Gasoline burned in an engine  
Lake freezing
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