Welcome to Chemistry ?

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Welcome to Chemistry ?

• Turn in electron configuration
• Notes on Bonding
• Practice

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Warm up

• Write noble gas configuration for Cu and Ag

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Introduction to Chemical Bonding

• Chapter 6, Section 1

Get ready to take notes
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What is a bond?

• A bond is an electrical attraction between
  valence electrons and protons of different atoms

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Why bond?

• Nature likes things easy (ie. low energy) and
  bonding causes atoms to be more stable.

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2 Main types of bonds

• Covalent electrons are shared between nonmetals
• Ionic electrons are transferred from cation to
  anion
• Might want to refresh your memory on
  electronegativity (p. 151)

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What determines type of bond???

• Electronegativity!
• Subtract the EN of the 2 atoms, then . . .
• If difference is equal to or more than 1.7
  ionic
• If difference is btwn 0.3 1.7 polar covalent
• If difference is less than 0.3 non-polar
  covalent

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What were those bonds again?

• Ionic electrons are transferred
• Polar Covalent electrons are shared, but not
  equally
• Non-polar covalent electrons are shared equally

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How bout some examples?

• What type of bond would form between the
  following elements?
• Hydrogen Sulfur
• Cesium Fluorine
• Carbon chlorine
• 2 Oxygen atoms

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Practice

• S and H
• 2.5-2.10.4
• polar covalent (b)
• Cs and F
• 4.0-0.73.3
• Ionic (c)
• C and Cl
• 3.0-2.50.5
• polar covalent (b)

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Practice

• Ca Cl
• 3.0-1.02.0
• Ionic (c)
• O O
• 3.5-3.50.0
• nonpolar covalent (a)
• Cl and Br
• 3.0-2.80.2
• nonpolar covalent (a)