CH 4 Earth Chemistry

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CH 4 Earth Chemistry
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Section 4.1

• Matter is anything that takes up space and has
  mass.
• An element is a substance that cannot be broken
  down into simpler, stable substances.
• Most common elements in Earths crust
• Oxygen 46.6
• Silicon 27.7
• Aluminum 8.1
• Also Iron, Calcium, Sodium, Potassium, Magnesium,
  others

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Isotopes

• Atoms with the same number of protons and
  electrons, but different numbers of neutrons
• Only Atomic Mass changes

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Periodic Table

• Go to Pg 86
• How is Atomic Mass Calculated?
• Based on the isotopes that have different masses,
  the Periodic Table uses the average of the
  different masses for each element.

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Practice Drawing Atoms

• What does the atom of Oxygen look like?
• What does the atom for Lithium look like?
• What does the atom for Boron look like?

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Why are the outer shell electrons important?

• These are the electrons that are used for
  reactions! The outermost electrons are able to
  react with other atoms
• Also Opposites attract
• Lets Identify the Valence Electrons for the
  groups of the Periodic Table

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Ions

• Charged Atoms-Allow the atoms of the elements to
  react
• Examples.
• Na Cl- ? NaCl
• Al 3 O 2- ? Al2O3
• Opposites Attract!!!

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Types of Bonds

• Covalent Bonds-A bond that is formed by the
  attraction between atoms that share electrons.
• Very strong Bond
• Ionic Bonds- The attractive force between
  oppositely charged ions that results from the
  transfer of electrons from one atom to another
• Very weak bond

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Types of Bonds

• Polar Covalent Bonds-In between an ionic and
  covalent bond- a Bond that does not equally share
  electrons and therefore creates a polar bond

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Mixtures

• Elements and compounds are generally mixed
  together.
• A mixture is a combination of two or more
  substances that are not chemically combined.
• Heterogeneous Mixture- mixture that is not
  uniformly distributed.
• Homogeneous Mixture- mixture that is uniformly
  distributed. IE a solution of Salt water.

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Chapter 5 Minerals

• Know the four criteria for minerals.
• Explain what a silicon-oxygen tetrahedron is and
  the different arrangements.
• Know the seven properties of minerals that help
  us identify them and be able to explain how to
  find hardness.

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Minerals

• Examples
• Rubies
• Gold Nugget
• Salt
• A mineral is a natural, usually inorganic solid
  that has a characteristic chemical composition,
  an orderly internal structure, and a
  characteristic set of physical properties.

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Minerals in Chihuahua
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• http//channel.nationalgeographic.com/episode/Vide
  os/08822_00

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Characteristics of Minerals

• Is it inorganic?
• Not made out of previously living things
• Does it occur naturally?
• Things made in nature not a lab
• Is it crystalline solid?
• Has a regular repeating crystalline structure
• Does it have a consistent chemical composition
• A common chemical formula
• Pg 103

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Properties of a Mineral

• Color
• Streak
• Luster
• Cleavage and Fracture
• Hardness
• Crystal Shape
• Density

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Read pg 109-112

• Create notes or an graphic organizer explaining
  in detail the 7 main properties of minerals.
• For bonus you can take notes or continue your
  graphic organizer on the Special Properties of
  Minerals from page 113 -114