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PCl3
• Simple Covalent molecules and Macromolecules:
• Covalent bonding leads to the formation of two types of molecules: Simple
Covalent molecules and Giant Covalent Structures (Macromolecules).
• Simple Covalent molecules contain a fixed number of atoms joined by strong
covalent bonds and are held together by weak intermolecular forces of
attraction. These intermolecular forces require a small amount of energy to
break.
• Simple Covalent molecules usually exist as gases/liquids while
Macromolecules exist as solids
Properties of Simple Covalent Molecules:
• Have low melting/boiling points (due to weak intermolecular forces.).
• Don’t conduct electricity
• Are (mostly) insoluble in water.
• Macromolecules have thousands of strong covalent bonds between atoms,
which require a tremendous amount of energy to break.
• There are four main macromolecules that you need to know about: