| (g) Covalent bonding |
| 1.44 know that a covalent bond is formed between atoms by the sharing of a pair of electrons |
| 1.45 understand covalent bonds in terms of electrostatic attractions |
1.46 understand how to use dot-and-cross diagrams to represent covalent bonds in:
- diatomic molecules, including hydrogen, oxygen, nitrogen, halogens and hydrogen halides
- inorganic molecules including water, ammonia and carbon dioxide
- organic molecules containing up to two carbon atoms, including methane, ethane, ethene and those containing halogen atoms
|
| 1.47 explain why substances with a simple molecular structures are gases or liquids, or solids with low melting and boiling point – the term intermolecular forces of attraction can be used to represent all forces between molecules |
| 1.48 explain why the melting and boiling points of substances with simple molecular structures increase, in general, with increasing relative molecular mass |
| 1.49 explain why substances with giant covalent structures are solids with high melting and boiling points |
| 1.50 explain how the structures of diamond, graphite and C60 fullerene influence their physical properties, including electrical conductivity and hardness |
| 1.51 know that covalent compounds do not usually conduct electricity |
