Atomic Architecture: Metals, Non-Metals and Noble Gases

All matter in the universe is constructed from 118 chemical elements, categorized into three distinct families based on their outermost electronic orbital configurations:

• A.
• Metals: Elements possessing 1, 2, or 3 electrons in their outermost valence energy level.
• Physical properties: Solid state at room temperature (with the sole liquid exception of Mercury Hg), lustrous metallic shine, high thermal and electrical conductivities, malleable (can be hammered into sheets), ductile (can be drawn into wires), and possess high melting points.

• Chemical behavior: During chemical reactions, metals tend to lose their valence electrons to reach the stable electron arrangement of the preceding noble gas.
• In doing so, the number of positive nuclear protons exceeds the remaining orbital electrons, turning the neutral atom into a positively charged Cation (e.g., ₁₁Na: 2,8,1 loses 1e⁻ -> Na⁺: 2,8; ₁₂Mg: 2,8,2 loses 2e⁻ -> Mg²⁺: 2,8; ₁₃Al: 2,8,3 loses 3e⁻ -> Al³⁺: 2,8).

• B.
• Non-Metals: Elements possessing 5, 6, or 7 electrons in their outermost shell (Hydrogen has 1 and Carbon has 4).
• Physical properties: Exist as solids (Carbon, Sulfur, Phosphorus), liquid (Bromine Br₂ is the only liquid non-metal), or gases (Oxygen, Nitrogen, Chlorine).
• They lack metallic luster, are brittle (fragment when hammered), and are thermal and electrical insulators (with the sole exception of Graphite/Carbon, which conducts electricity).

Chemical behavior: During chemical reactions with metals, non-metals tend to gain electrons to complete an octet, becoming negatively charged Anions (e.g., ₁₇Cl: 2,8,7 gains 1e⁻ -> Cl⁻: 2,8,8; ₈O: 2,6 gains 2e⁻ -> O²⁻: 2,8; ₇N: 2,5 gains 3e⁻ -> N³⁻: 2,8).

• C.
• Noble (Inert) Gases: Elements whose outermost energy level is completely saturated with 8 electrons (Helium has 2 in its single K-shell).
• Members: Helium He, Neon Ne, Argon Ar, Krypton Kr, Xenon Xe, Radon Rn.
• They do not participate in chemical reactions under standard conditions, have a valency of zero, and exist exclusively as monoatomic gases.