1. Lewis Diagrams
Lewis diagrams illustrate chemical bonding by showing only an atom’s valence electrons and the chemical symbol.
See page 178
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2. Lewis Diagrams
Lewis diagrams illustrate chemical bonding by showing only an atom’s valence electrons and the chemical symbol.
Dots representing electrons are placed around the element symbols at the points of the compass (north, east, south, and west).
See page 178
(c) McGraw Hill Ryerson 2007

3. Lewis Diagrams
Lewis diagrams illustrate chemical bonding by showing only an atom’s valence electrons and the chemical symbol.
Dots representing electrons are placed around the element symbols at the points of the compass (north, east, south, and west).
Electron dots are placed singly until the fifth electron is reached then they are paired.
See page 178
(c) McGraw Hill Ryerson 2007

4. Lewis Diagrams
Lewis diagrams illustrate chemical bonding by showing only an atom’s valence electrons and the chemical symbol.
Dots representing electrons are placed around the element symbols at the points of the compass (north, east, south, and west).
Electron dots are placed singly until the fifth electron is reached then they are paired.
See page 178
(c) McGraw Hill Ryerson 2007

5. Forming Compounds (continued)
Covalent bonds are formed between two or more non-metals.
Electrons are shared between atoms.
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6. Forming Compounds (continued)
Covalent bonds are formed between two or more non-metals.
Electrons are shared between atoms.
hydrogen
fluorine +
electrons are shared
Hydrogen fluoride
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7. Lewis Diagrams of Covalent Bonds
Lewis diagrams can also represent covalent bonds.
Like Bohr diagrams, valence electrons are drawn to show sharing of electrons.
The shared pairs of electrons are usually drawn as a straight line.
See page 179
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8. Lewis Diagrams of Diatomic Molecules
Diatomic molecules, like O2, are also easy to draw as Lewis diagrams.
• •
• • O
Several non-metals join to form diatomic molecules.
Valence electrons are shared, here in two pairs.
This is drawn as a double bond.
See page 180
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9. BrINClHOF (say Brinckle-hoff)
Diatomic molecules, like O2, are also easy to draw as Lewis diagrams.
DIATOMIC MOLECULES:
hydrogen, nitrogen, oxygen, fluorine, chlorine, bromine and iodine
Memory trick:
HONClFIBr (say HONKLE-fibber) OR
BrINClHOF (say Brinckle-hoff)
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10. Lewis Diagram for Ionic Compounds – metal and nonmetal
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11. Names and Formulas of Covalent Compounds
Covalent compounds, also called molecules, rely on the chemical formula to reveal the components of the molecule.
Covalent compounds are made up of two or more non-metals.
See page 193
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12. Names and Formulas of Covalent Compounds
Covalent molecules have subscripts that show the actual number of atoms in the molecule.
See page 193
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13. Naming Binary Covalent Compounds
Binary covalent compounds (two non-metal atoms) use a system of prefixes.
Covalent compounds may have many or few atoms sharing electrons.
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14. Naming Binary Covalent Compounds
Prefixes are often used before the atom name to indicate the number of atoms in the molecule.
CO = carbon monoxide, CO2 = carbon dioxide
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15. Naming Binary Covalent Compounds
Prefixes are often used before the atom name to indicate the number of atoms in the molecule.
CO = carbon monoxide, CO2 = carbon dioxide
Write the most metallic atom (farthest left) first
Add -ide to the end of the second atom’s name
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16. Naming Binary Covalent Compounds
What is the chemical formula for the molecule trinitrogen tetrachloride?
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17. Naming Binary Covalent Compounds
What is the chemical formula for the molecule trinitrogen tetrachloride?
N3Cl4
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18. Naming Binary Covalent Compounds
What is the name of the molecule Si3P6?
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19. Naming Binary Covalent Compounds
What is the name of the molecule Si3P6?
Trisilicon hexaphosphide
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