Molecular compounds

All compounds contain atoms of more than one element, chemically joined together by bonds. The properties of a compound are influenced by its atoms and by its type of bonding.

Some compounds exist as molecules. They have covalent, simple molecular structures. An example of this is water. One molecule of water always contains one atom of oxygen covalently bonded to two atoms of hydrogen.

The covalent bonds in a water molecule are strong forces of attraction. However, there are also weak forces of attraction between molecules called intermolecular forces. These intermolecular forces hold water molecules together and must be overcome when turning liquid water into a gas. Small, simple molecules such as…