Acceptor atom - the atom that accepts both bonding electrons from the other atom in a dative covalent bond

Ball-and-stick model - a molecular model of a chemical substance which is to display both the three-dimensional position of the atoms and the bonds between them in a molecule

Bond pair electrons - the pair of electrons shared between two atoms

Covalent bond - formed when one or more pairs of outermost shell electrons are shared between two atoms. It is the strong electrostatic forces of attraction between the shared electrons and the two positively

Covalent compound - a compound in which its atoms of different elements share electrons with each other

Dative covalent bond - a covalent bond in which the bond pair electrons are provided by the same atom

Diatomic molecule - a molecule which consists of two atoms

Double bond -  a type of linkage between atoms in which two pair of electrons are shared equally

Formula mass - the sum of the relative atomic masses of all atoms making up one formula unit of an ionic compound

Hydroxonium ion or hydronium ion - formed when a water molecule and a hydrogen ion combine via dative covalent bonding

Lone pair electrons - the pair of electrons in the outermost shell that is not involved in bonding

Molecular formula - a chemical formula that indicates the actual numbers and kinds of atoms in a molecule, but not the chemical structure

Molecular model - models which represent molecules and examples are ball-and-stick models and space-filling models

Molecule - Atoms of non-metallic elements can join together to form groups called molecules

Monoatomic molecule - a molecule which consists of one atom only

Relative molecular mass - the sum of the relative atomic masses of all atoms present in one molecule of an element or compound

Single bond - a bond in which one pair of electrons is shared

Triple bond -  a type of linkage between atoms in which three pair of electrons are shared equally