Giant covalent substances have many atoms joined together by covalent bonds. Diamond, graphite and graphene are forms of carbon with different giant covalent structures.
polymerA large molecule formed from many identical smaller molecules known as monomers. have very large moleculeA collection of two or more atoms held together by chemical bonds.. The atoms in a polymer molecule are joined together by strong covalent bondA bond between atoms formed when atoms share electrons to achieve a full outer shell of electrons. in long chains. There are variable numbers of atoms in the chains of a given polymer. One example of a polymer is poly(ethene).
Figure caption,
A short section of a poly(ethene) molecule. Poly(ethene) molecules contain thousands of carbon atoms joined together in a chain
Figure caption,
This diagram also represents poly(ethene). The value of 'n' varies, but it is always a large number
Properties of polymers
The intermolecular forcesWeak attractive forces between molecules. When a simple molecular substance melts or boils, it is the intermolecular forces that are broken (not the covalent bonds in each molecule). between polymer molecules are strong compared to the intermolecular forces between small molecules. This means that polymers melt at higher temperatures than substances with small molecules. They are solids at room temperature.