lewis dot diagrams show where electrons and bonds exist in covalent compounds. [
TRANSCRIPT
Lewis Dot DiagramsLewis Dot Diagrams
• Show where electrons and bonds exist in covalent compounds.
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Lewis Dot DiagramsLewis Dot Diagrams
• Dots are used to show valence electrons for specific atoms.
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Lewis Dot DiagramsLewis Dot Diagrams
• Electrons are “shared” to form bonds and satisfy the octet rule.
• Example: H2O
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Lewis Dot DiagramsLewis Dot Diagrams
• Example: NH3
• 1st – Count up all valence electrons
• N = 5 e-
• H = 1 e- x 3 = 3 e-
• 8 total valence electrons
Lewis Dot DiagramsLewis Dot Diagrams
• 2nd – Draw individual dot diagrams
• Hint – place 1 per side to start.
N
HH H
Lewis Dot DiagramsLewis Dot Diagrams
• 3rd – Connect lone electrons to satisfy octet rule and form “bonds”
• Remember, H only wants 2 e- !
N
HH H
Lewis Dot DiagramsLewis Dot Diagrams
• Last Step – Draw a “final” picture with lines (2 shared electrons)
• Make sure that all valence electrons are accounted for!
• Any electrons that are not in bonds are called unshared, or lone pairs.
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8 Total Electrons!
Lewis Dot DiagramsLewis Dot Diagrams
• Some compounds will share more than 2 electrons, so multiple bonds are drawn.
• Example: O2
Lewis Dot DiagramsLewis Dot Diagrams
• Exceptions to the Octet Rule:
• Boron (6 e-)
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Lewis Dot DiagramsLewis Dot Diagrams
• Phosphorus (10 e-)
• Sulfur (12 e-)
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