Giant covalent molecules

• Diamond, graphite and graphene are forms of carbon with different giant covalent structures.
• Silicon dioxide, often called silica, is an example of a substance with a giant covalent structure.
• Silica is the main compound found in sand and is an example of a substance with a giant covalent structure.
• Silica has a giant covalent structure containing silicon atoms (grey) and oxygen atoms (red).
• Substances with giant covalent structures are solids at room temperature and have very high melting points and boiling points.
• Most substances with giant covalent structures cannot conduct electricity, but graphite, a form of carbon which can conduct electricity, is an exception.
• The three states of matter are solid, liquid and gas.
• Ionic compounds are a type of salt.
• Small molecules contain a fixed number of atoms.
• Metals and alloys are a type of material.