CH 18 3 IONIC BONDS

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CH 18 3IONIC BONDS

• STANDARD 3- MATTER
• STANDARD 7- THE PERIODIC TABLE
• MOSTLY STANDARD 5- REACTIONS

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A. ELECTRON TRANSFER

• 1. When atoms have fewer than 4 electrons, they
  can transfer them to other atoms that have more
  than 4.

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A. ELECTRON TRANSFER

• 2. Atoms either gain or lose electrons to become
  stable.

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A. ELECTRON TRANSFER

• 3. An ion is an atom or group of atoms that has
  become electrically charged.
• a. an ion has an uneven number of protons and
  electrons
• b. lose an electron to be charged
• c. gain an electron to be - charged

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B. FORMING AN IONIC BOND

• and charges attract each other just like
  magnets
• An ionic bond is the attraction between 2
  oppositely charged ions
• The resulting compounds are electrically neutral
• Look at page 581

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C. POLYATOMIC IONS

• Poly means many
• Ions made of more than 1 atom are polyatomic
• a. example CO3 2-

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D. NAMING IONIC COMPOUNDS

• The name of the ion goes first
• The name of the ion goes last
• See page 580

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E. PROPERTIES OF IONIC COMPOUNDS

• Properties include crystal shape, high melting
  points, and electrical conductivity.
• Crystal shape
• Ions form orderly, 3-d arrangements called
  crystals as solids.
• In an ionic compound, every ion is attracted to
  ions near it that have an opposite charge.

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E. PROPERTIES OF IONIC COMPOUNDS

• b. high melting point
• 1. Salt melts at 801. C
• 2. Ionic bonds are strong enough to cause
  all ionic compounds to be solids at room temp

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E. PROPERTIES OF IONIC COMPOUNDS

• c. electrical conductivity
• 1. When ionic compounds dissolve in water,
  they conduct electricity.
• 2. This is due to the and ions
  separating in the water