Properties of covalent substances
Simple molecular covalent substances
Simple molecular covalent substances include gases such as hydrogen, methane, oxygen and carbon dioxide, and liquids such as water. These substances have low melting and boiling points because there are only weak forces between neighbouring molecules.
An electric current is a flow of charged particles. The atoms in simple molecular covalent molecules have not lost or gained electrons, so there are no charged particles that can move around. These substances are poor conductors of electricity.
Giant molecular covalent substances
Some covalent compounds from giant molecular covalent substances. These consist of billions of atoms all joined together by covalent bonds. Most gain molecular substances have high melting and boiling points. This is because al the atoms by strong covalent bonds, and a…