To learn about ionic and covalent bonds and explain how they are formed

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Objectives

1. To learn about ionic and covalent bonds and
   explain how they are formed
2. To learn about the polar covalent bond
3. To understand the nature of bonds and their
   relationship to electronegativity
4. To understand bond polarity and how it is related
   to molecular polarity

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A. Types of Chemical Bonds

• Bond force that holds groups of atoms together
  and makes them function as a unit
• Bond energy energy required to break a chemical
  bond

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A. Types of Chemical Bonds
Ionic Bonding

• Ionic compound results when a metal reacts with a
  nonmetal

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A. Types of Chemical Bonds
Covalent Bonding

• A covalent bond results when electrons are shared
  by nuclei

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A. Types of Chemical Bonds
Covalent Bonding

• A polar covalent bond results when electrons are
  shared unequally by nuclei

• One atom attracts the electrons more than the
  other atom

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B. 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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B. Electronegativity

• The polarity of a bond depends on the difference
  between the electronegativity values of the atoms
  forming the bond

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B. Electronegativity
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C. Bond Polarity and Dipole Moments

• A dipole moment results when a polar molecule has
  a center for positive charge separate from a
  center for negative charge

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C. Bond Polarity and Dipole Moments

• Water molecule dipole moment

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C. Bond Polarity and Dipole Moments

• The polarity of water affects its properties

• Permits ionic compounds to dissolve in it

• Causes water to remain liquid at higher
  temperature