- Physical Sciences
a measure of the amount of substance per unit volume. Unit: mol.dm-3
the energy level, or shell, of an atom that contains the valence electrons.
the heat of reaction or the change in heat when reactants form products during a chemical...
the forces between atoms within molecules: covalent, polar covalent, dative covalent, ionic and...
a compound that conducts electricity when it is in aqueous solution.