1. • Explain how a permanent dipole can result in a polar bond.
Week 8
• Describe electronegativity in terms of an atom attracting bonding electrons in a covalent bond.
• Explain how a permanent dipole can result in a polar bond.
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2. Week 8 Non-polar bonds © Pearson Education Ltd 2008
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3. Week 8 The polar bond in H-Cl © Pearson Education Ltd 2008
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4. CCl4 is a non-polar molecule
Week 8
CCl4 is a non-polar molecule
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5. Pauling electronegativity values across the Periodic Table
Week 8
Pauling electronegativity values across the Periodic Table
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6. Range of bonding from covalent to ionic
Week 8
Range of bonding from covalent to ionic
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7. Week 8
• Describe intermolecular forces in terms of permanent and instantaneous (van der Waals’ forces) dipoles.
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8. Permanent dipole–dipole forces between HCl molecules
Week 8
Permanent dipole–dipole forces between HCl molecules
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9. Week 8 van der Waals’ forces © Pearson Education Ltd 2008
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10. Week 8
• Describe hydrogen bonding between molecules containing –OH and –NH groups.
• Describe and explain the anomalous properties of water resulting from hydrogen bonding.
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11. The key features for hydrogen bonding
Week 8
The key features for hydrogen bonding
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12. Hydrogen bonding in water
Week 8
Hydrogen bonding in water
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13. The ice lattice is an open network of H2O molecules
Week 8
The ice lattice is an open network of H2O molecules
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14. In DNA, three hydrogen bonds link C and G
Week 8
In DNA, three hydrogen bonds link C and G
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15. In DNA, two hydrogen bonds link A and T
Week 8
In DNA, two hydrogen bonds link A and T
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16. Week 8 Double helix in DNA © Pearson Education Ltd 2008
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