Understanding Periodic Table Organisation and Covalent Molecular Elements
The periodic table arranges elements in horizontal rows (periods) by increasing atomic number and vertical columns (groups) by similar properties. Elements in the same group behave similarly because they have the same number of outer electrons, making it dead easy to predict how they'll react.
Covalent molecular structures are made up of separate molecules held together by weak intermolecular forces. The actual covalent bonds form when non-metal atoms share electrons to achieve a stable outer electron arrangement (like noble gases). Think of it as atoms "holding hands" with shared electrons.
Most covalent molecular elements are diatomic (two atoms joined together): hydrogen (H₂), nitrogen (N₂), oxygen (O₂), fluorine (F₂), and chlorine (Cl₂). Some elements form larger molecules like phosphorus (P₄) and sulfur (S₈).
Quick Tip: Covalent molecular elements have low melting points, low densities, and don't conduct electricity because there are no free-moving charged particles.
