5.2.2.4 Properties of small molecules
1. Low melting points and boiling points
Substances that consist of small molecules
have relatively low melting points and boiling points
are usually gases or liquids
Because:
there are weak intermolecular forces
between molecules
which require little energy to overcome / break
The intermolecular forces increase with the size of the molecules, so larger molecules have higher melting and boiling points.
2. Do not conduct electricity
Because the molecules do not have an overall electric charge.