Objectives

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Objectives

1. To learn the various features of the periodic
   table
2. To learn some of the properties of metals,
   nonmetals and metalloids
3. To learn the natures of the common elements

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A. Introduction to the Periodic Table

• The periodic table shows all of the known
  elements in order of increasing atomic number.

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A. Introduction to the Periodic Table

• The periodic table is organized to group elements
  with similar properties in vertical columns.

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A. Introduction to the Periodic Table

• Most elements are metals and occur on the left
  side.

• The nonmetals appear on the right side.
• Metalloids are elements that have some metallic
  and some nonmetallic properties.

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A. Introduction to the Periodic Table

• Physical Properties of Metals

1. Conduct heat and electricity easily
2. Malleable (can be hammered into thin sheets)
3. Ductile (can be pulled into wires)
4. A lustrous (shiny) appearance

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B. Natural States of the Elements

• Most elements are very reactive.
• Elements are not generally found in uncombined
  form.
• Exceptions are
• Noble metals gold, platinum and silver
• Noble gases Group 8

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A. Electron Arrangements in the First 18 Atoms
on the Periodic Table
Classifying Electrons

• Valence electrons electrons in the outermost
  (highest) principal energy level of an atom
• Core electrons inner electrons
• Elements with the same number of valence
  electrons show very similar chemical behavior.

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Valence Electrons

• The labels for groups 1, 2, 3, 4, 5, 6, 7, 8
  indicate the total number of valence electrons
  for the atoms of the elements in these groups
• They are called the representative elements

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B. Electron Configurations and the Periodic Table

• Orbital filling and the periodic table

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C. Atomic Properties and the Periodic Table
Atomic Size

• Size tends to increase down a column.
• Size tends to decrease across a row.

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C. Atomic Properties and the Periodic Table

• Ionization Energies
• Ionization Energy energy required to remove an
  electron from an individual atom (gas)

• Tends to decrease down a column
• Tends to increase across a row

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Electronegativity

• Electronegativity the relative ability of an
  atom in a molecule to attract shared electrons to
  itself
• Increases from left to right across a period
• Decreases down a group of representative elements

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Ionic bonding and Size

• Metallic ions are always smaller than the parent
  atom

• Non-metallic ions are always larger than the
  parent atom