Chemical Bonding

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Chemical Bonding

• The Formation of Compounds
• CA Standards 3b,c and 6c

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Introduction to Bonding Video
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Lewis Theory

G.N. Lewis (1875-1946) recognized valence
electrons bond from one atom to another electron
transfer resulting in ionic bondssharing
electrons resulting in covalent bondsoverlapping
electrons resulting in metallic bonds
The attraction between electrons of one atom to
the nucleus of another atom contribute to what is
known as chemical bonds.


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A. Why bonding?

• All atoms want a filled outer ring to be STABLE
  atoms (non-reactive)
• Atoms bond to fill their outer electron ring
• Stablefull set of valence electrons (electrons
  in the last ring)
• Atoms that already have a filled outer ring are
  the noble gases
• Bonding creates compounds like water H2O and
  glucose sugar C6H22O11

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B. Two Types of Bonding

• 1 Ionic
• Complete transfer of electrons from one atom to
  another
• Creates charged particles (called ions)
• Opposite charges attract
• Occurs between a metal and a non-metal atom
• Gives a compounds a high melting/boiling point

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Ionic Bonding Video
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• 2 Covalent Bonding
• Atoms share electrons
• Occurs between a non-metal and a non-metal atom

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Properties of Covalent Bonds

• Low melting and boiling points
• Brittle solids

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Covalent Bonding Video
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3 Metallic Bonding

• -Electrons overlap
• -Occurs between two metal atoms
• -Gives metals their properties (malleability,
  ductility, conductivity)

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Metallic Bonding Video
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Lewis Dot Structures

• Lewis structures show the valence electrons as
  dots arranged around the atomic symbol.
• hydrogen
• sodium
• chlorine

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The Octet Rule

• Atoms tend to gain, lose, or share electrons
  until they have eight valence electrons.

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Ionic and Molecular Compounds

• Formation of sodium chloride

• Formation of hydrogen chloride

A metal and a nonmetal transfer electrons to form
an ionic compound. Two nonmetals share electrons
to form a molecular compound.
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Learning Check

• Draw electron dot diagrams for
• Hydrogen
• Carbon
• Nitrogen
• Oxygen
• These elements form life and make up cells, DNA,
  carbohydrates and proteins