Simple Covalent Molecule

Key Stage 4

Simple covalent molecules are small molecules in which the atoms are held together by covalent bonds.

Simple covalent molecules are simple in that they have only a small number of atoms.

Simple covalent molecules can be elements or compounds.

The covalent bonds in a simple covalent molecule can be represented with a Dot and Cross Diagram.

Simple Covalent Molecular Elements

The two Hydrogen atoms each share one electron with each other.	The two Oxygen atoms each share two of their electrons with one another.	The two Nitrogen atoms each share three of their electrons with one another.

Simple Covalent Compounds

Each Oxygen shares two of its electrons with the Carbon atom while the Carbon atom shares two electrons with each Oxygen atom.	Each Hydrogen atom shares its only electron with the Oxygen atom and the Oxygen shares one of its electrons with each Hydrogen atom.	Each Hydrogen atom shares its only electron with the Carbon atom and the Carbon atom each of its 4 electrons with the Hydrogen atoms.

The physical properties of substances made of simple covalent molecules are determined by the the covalent bonds within molecules and the intermolecular bonds between molecules.

The boiling point and melting point of a simple covalent' substance are determined by the strength of intermolecular bonds. The stronger the intermolecular bonds the higher the boiling point and melting point.

Substances made of simple covalent molecules are usually poor electrical conductors because charged particles such as electrons or ions are not free to move from one place to another.

Substances made of simple covalent molecules are usually poor thermal conductors because electrons are not free to move around the material.