To learn to distinguish between mixtures and pure substances

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Objectives

1. To learn to distinguish between mixtures and pure
   substances
2. To learn methods of separating mixtures

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A. Mixtures and Pure Substances

• Matter can be classified as a mixture or a pure
  substance.

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A. Mixtures and Pure Substances

• Pure Substances

• A pure substance always has the same composition.
  
• Pure substances are of two types

• Elements which cannot be broken down chemically
  into simpler substances
• Compounds in which all the components are the
  same (but could be chemically broken down into
  elements)

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A. Mixtures and Pure Substances

• Mixtures

• A mixture has variable composition
• A homogeneous mixture has the same properties
  throughout. Often called a solution
• A heterogeneous mixture has different properties
  in different parts of the mixture.

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B. Separation of Mixtures

• Mixtures can be separated into pure substances by
  various means.

• distillation

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An Oil Refinery uses Distillation to separate
crude oil into useful fractions
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B. Separation of Mixtures

• Mixtures can be separated into pure substances by
  various means.

• filtration

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Separation Techniques

• How would you separate..?
• Two liquids that boil at different temperatures
• Sand and water
• Oil and iron filings
• Oil and paper
• Stones and peanuts
• A pile of sticks and dry leaves
• A mixture of dogs and cats

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• Summary The Organization of Matter