Atomic Structure and Nuclear Energy Fundamentals

Atomic Theory Evolution

John Dalton proposed that matter is composed of distinct masses that combine to form different compounds. He defined the atom as an indivisible and indestructible particle.

J.J. Thomson discovered the electron and defined the atom as a sphere with a positive charge, where negatively charged electrons were distributed.

E. Rutherford discovered that the atom consisted of a dense nucleus formed by protons with a positive charge, where electrons revolve around it with a negative charge.

Niels Bohr advanced Rutherford's model and discovered that electrons are found in orderly orbits.

Subatomic Particles

• Proton: A subatomic particle with a positive charge and a mass of 1.6726231 × 10^-27 kg.
• Neutron: A subatomic particle with no charge and a mass similar to the proton.
• Electron: A subatomic particle with a negative charge and a mass of 9.10 × 10^-31 kg.

Atomic Properties

Atoms: These are the smallest units of matter. Atoms are composed of three subatomic particles: the proton, the neutron, and the electron.

Ions: Atoms that are electrically charged. An ion can be a cation (positive charge) or an anion (negative charge).

Isotopes: Atoms with the same atomic number but different atomic weights; their nuclei have the same number of protons but different numbers of neutrons.

Chemical Bonding

• Ionic bond: Corresponds to the union of ions of opposite signs via electrostatic attraction. It is typically formed with a metal.
• Covalent bond: Occurs when two atoms share one or more pairs of electrons.
• Metallic bond: Typical of metals, occurring between elements of equal or lower electronegativity.

Nuclear Processes

Natural Radioactivity: A process in which the nucleus loses particles such as photons or neutrons.

Nuclear Energy Production: There are different ways to produce nuclear energy, utilizing nuclear fission and nuclear fusion.

• Nuclear Fission: The process by which a heavy nucleus splits into two or more lighter nuclei.
• Nuclear Fusion: A reaction in which two atomic nuclei are converted into a heavier nucleus.