not classified by their phases, because several can exist i

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MIXTURES, ELEMENTS, COMPOUNDS AND SOLUTIONS

• CHEMISTRY
• MS. ZIMMER
• 2005

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CLASSES OF MATTER

• Matter exists as mixtures, solutions, elements or
  compounds
• Classified by their make up
• Not classified by their phases, because several
  can exist in more than one phase.

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CLASSES OF MATTER REVIEW

• What are the four classes of matter?
• Mixtures, solutions, compounds, elements
• How are the classes classified?
• They are classified by their make up.
• Why isnt matter classified by their phases?
• They are not classified by their phases because
  some matter can exist in more than one phase.

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MIXTURES

• Mixtures consists of two or more substances
• Mixture are not chemically combined
• Each substance in a mixture maintains its
  physical properties

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PROPERTIES OF MIXTURES

• Substances in a mixture are not chemically
  combined.
• Sugar dissolved in water is still sugar
• Substances may change in physical appearance, but
  the chemical properties do not.
• You cant see the sugar in the water but it is
  there.

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PROPERTIES OF MIXTURES CONT.

• Substances in a mixture can be present in any
  amount.
• There can be a little sugar or a lot of sugar
  dissolved in the water.
• Substances in a mixture can be separated by
  physical means.
• Dissolve water and you have the sugar left.
• No chemical reaction needed to separate mixtures

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HETEROGENEOUS MIXTURE

• least-mixed
• Particles are large enough to see
• Does not appear the same throughout
• Easy to separate the particles
• Not only solid-solid mixtures
• Can be liquid-liquid

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HOMOGENEOUS MIXTURES

• Well-mixed
• Particles are small and not easily recognizable
• Do not settle when the mixture stands
• Particles are mixed
• Appears to be the same throughout

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COLLOIDS

• Particles are mixed together but are not
  dissolved
• Particles are large and kept suspended
• Particles will not separate when left standing
• Bombarded by other particles
• Often appears cloudy

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SOLUTIONS

• Homogeneous mixture formed when one substance
  dissolves into another.
• Solutions have a substance that is dissolved
  called the solute
• Solutions have a substance that does the
  dissolving called a solvent

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SOLUTIONS CONT.

• Particles in a solution are not visible
• Hard to separate physically
• Solutions appear to be clear
• Particles are evenly spread out

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SOLUBILITY

• A substance that dissolves in water is soluble
• Salt, sugar
• A substance that cant dissolve in water is
  insoluble
• Mercury, oil

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SOLUBILITY CONT.

• SOLUBILITY OF GASES
• As the temperature increases, the solubility of
  the gas decreases
• The warmer the soda, the less fizz due to less
  CO2 in solution

• SOLUBILITY OF SOLIDS
• As the temperature of a solvent increases, the
  solubility of the solute increases
• More sugar can dissolve in warm water than in
  cold water

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ALLOYS

• Metal solutions
• Solids dissolved in solids
• Gold jewelry is a solid solution of gold and
  brass
• Brass is a solution of copper and zinc

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REVIEW

• What is a mixture?
• A combination of 2 or more substances mixed
  together but not chemically combined
• How does a heterogeneous mixture differ from a
  homogeneous mixture?
• Heterogeneous mixtures have large particles and
  do not appear the same throughout
• Homogeneous mixtures have small particles that
  are well blended and are the same throughout.

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Review Cont.

• What is a colloid?
• A homogeneous mixture where the particles are
  mixed together but are not dissolved and are
  permanently suspended
• What is a solution?
• A type of homogeneous mixture formed when one
  substance dissolves in another substance.
• What are the two parts of a solution?
• Solute (what dissolves) and solvent (what does
  the dissolving)

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Review Cont.

• What are two properties of a solution
• The particles are not easily separated
• Particles are so small they are not visible
• What is solubility?
• The ability to absorb in water
• What is an alloy? Give an example.
• A metal solution of two or more metals.
• Gold jewelry, brass, stainless steel