The atom, the basic constituent element of matter, is made up of a nucleus surrounded by negatively charged electrons. Inside the atomic nucleus is a mixture of positively charged protons and electrically neutral neutrons. All atomic electrons bind to the nucleus by electromagnetic force. A mass of electrons bonded together will form individual molecules. An atom with an equal number of protons and electrons will remain neutral. An ion has a positive or negative charge, either from a lack of electrons or an excess of electrons. The number of protons determines the formation of chemical elements, while the number of neutrons determines the isotope of the element. Most of the atom's mass has a compacted concentration in its nucleus; however, protons and neutrons have approximately the same mass. Electrons bound to atoms hold a percentage of stable energy levels, also called orbitals, which undergo transient processes by absorbing or omitting photons with equal energy levels. Electrons determine the chemical properties of an element, thereby influencing the magnetic properties of an atom. Subatomic particles, the scientific term for electrons, protons and neutrons, are the individual atomic components that determine the classification of certain molecules. Electrons have a negative electric charge that is too small to be measured by modern techniques. Protons have a positive charge and a mass much greater than that of the electron. Neutrons have no electrical charge. Protons and neutrons have a composition of elementary particles called quarks, a member of the fermion group of particles. There are six different types of quarks, each with a fractional electric charge. Protons have two up quarks and one down quark, while neutrons have one up quark and two do...... middle of paper ......Matter (PDF): A comprehensive resource detailing the science behind the matter around us, including the composition of atoms and the functional movement of all molecules.Miami Science Museum: The Atom Family: A science project idea illustrating the composition of atoms.New York Hall of Science: All About Molecules : Molecules are small particles that make all organic and non-organic materials.SK Online: Atoms and Molecules: A science lesson explaining the basic elements of life and the composition of all molecules.American Physical Society: From Atoms to Molecules (and back): Developments in physics have led to laser technology that can combine and deconstruct atoms into molecules and molecules into atoms. 4-H Project: Fun with Atoms (PDF): A lesson plan and science project that will help illustrate the composition of atoms into molecules..