- KCl
- NaCl
- CaCl₂
- Na₂CO₃
Sodium chloride (NaCl), commonly known as table salt, is an ionic compound composed of sodium cations (Na⁺) and chloride anions (Cl⁻) in a 1:1 ratio. This formula represents the simplest empirical formula, though actual crystal structure shows each Na⁺ surrounded by six Cl⁻ ions in a cubic lattice (face-centered cubic). Common salt is essential for human life, maintaining fluid balance, nerve transmission, and muscle function. It is the primary seasoning agent worldwide and historically served as a valuable preservative before refrigeration. Sources include sea water evaporation, rock salt mining (halite), and salt lakes. Beyond culinary uses, NaCl is crucial in chemical industry for producing chlorine gas, sodium hydroxide, and sodium carbonate. It lowers the freezing point of water (road de-icing) and raises boiling point. The name “sodium” derives from Arabic “suda” (headache) via Latin “sodanum” (headache remedy), while “chloride” comes from Greek “chloros” (greenish-yellow), referring to chlorine gas. Understanding NaCl’s properties explains its widespread applications and biological necessity.
