CHEMICAL BONDS

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CHEMICAL BONDS

• The force that holds two atoms together in a
  compound

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CHEMICAL BONDS

• Electronegativity The relative tendency of an
  atom to attract electrons to itself when bonded
  to another atom.
• The most active metals have the lowest
  electro-negativity.
• Fluorine has the highest.
• Bond strength The energy needed to break the
  bond.

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BONDS

• The greater the difference in
• electronegativity the stronger the bond.

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COVALENT BONDS

• Shared electrons
• Electronegativity difference less than 1.67
• Low melting points
• Do not conduct electricity
• Are brittle

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Unequal Sharing

• Electrons are not always shared equally in a
  covalent bond
• This has to do with the relative size of the
  atoms, If one atom is much larger then it will
  have a stronger attraction
• These type of covalent bonds are called polar
  bonds

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Unequal sharing

• They are polar because one end of the molecule is
  more negative than the other examples Water, HCl
• It is easier to determine if a compound is
  nonpolar two atoms exactly alike share atoms
  equally ex O2 compounds that are symmetrical CCl4

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IONIC BONDS

• High melting points
• Ability to conduct electricity
• Electronegativity differences greater than 1.67
• Soluable in water
• Usually crystalline as sharply defined particles
• Exchange electrons

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METTALIC BONDS

• Are solids that conduct electricity
• Shiny
• Malleable
• Delocalized electron cloud
• Very high melting points
• Sea of electrons

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Substances Using Bond Types