Compounds, Mixtures, and Reactions

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Compounds, Mixtures, and Reactions

• Unit II-Part 5

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Classifying Matter
Matter
Pure Substances
Mixtures
Homogeneous
Heterogeneous
Elements
Compounds
Rocky Road ice cream, muddy water
milk, tea
Fe, O
H2O, CO2
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What is a Pure Substance?

• A pure substance is a classification of matter
  that includes both elements and compounds
• Pure substances cannot be separated by physical
  means such as distillation, filtration, or
  chromatography

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Elements

• We have already studied elements
• An element is made of one kind of atom
• Found on the periodic table

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What Is A Mixture?

• A mixture is the physical combination of 2 or
  more substances
• It is important to understand that a mixture is
  not chemically combined
• Mixtures can be separated by physical means such
  as filtration, distillation, and chromatography
• Mixtures can be divided into 2 groups
• Homogenous mixtures
• Heterogeneous mixtures

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How Do Mixtures Form?

• Mixtures form by physically junking 2 or more
  substances together
• Remember no chemical change is occurring
• The formation of a mixture is not a result of
  lowering energy

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What Is a Homogenous Mixture?

• A homogeneous mixture is a mixture that is evenly
  distributed
• Homogeneous mixtures are commonly called
  solutions.
• Solution Solute Solvent
• Solute stuff being dissolved
• Solvent stuff doing the dissolving
• The solvent is present in greater quantity
• The solute is present in the lesser quantity
• Ex Salt water Saltsolute, Watersolvent

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What Is a Heterogeneous Mixture?

• A heterogeneous mixture is a mixture that is
  unevenly distributed.
• Examples
• Iced tea The ice is floating at the top and
  therefore is not evenly distributed throughout
  the tea
• Chex Mix You may find a different number of
  pretzels or Chex cereal in each handful
  therefore, the mixture is unevenly distributed

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How Are Mixtures Important To My Life?

• We encounter mixtures everywhere in our lives
• Where would you be without
• Ice cream
• Kool-aid
• Shampoo
• Soup
• Milk
• Orange juice