2.9 - Simple & Giant Covalent Structures

The properties of simple molecular substances

Simple molecular substances are elements and compounds made of small molecules, such as hydrogen, water, carbon dioxide, methane and ammonia.

Low melting and boiling points

• Most simple molecular substances have low melting and boiling points.
• Many are gases or liquids at room temperature, and the solid ones melt at relatively low temperatures.

They don't conduct electricity

• Simple molecular substances do not conduct electricity in any state (solid, liquid, or gas).
• The molecules carry no overall charge, and there are no mobile ions or delocalised electrons to carry a current.