Salt (chemistry)
A salt is an ionic compound composed of cations and anions. Many salts form when an acid’s hydrogen ions are replaced by other cations.
Ion: An atom or molecule with a net electric charge from gaining or losing electrons. Salts are assembled from positively and negatively charged ions.
Acid–base reaction: A reaction involving proton transfer or, more broadly, the reaction of an acid with a base. Neutralization can produce a salt alongside water or another product.
Electrolyte: A substance that produces mobile ions when dissolved or melted and thereby conducts electricity. Dissolved salts commonly act as electrolytes by supplying mobile ions.
Molecular compound: A substance whose atoms are joined primarily by covalent bonds into discrete molecules. Unlike typical salts, molecular compounds consist of bonded molecules rather than ionic lattices.
Calcium carbonate: The ionic compound CaCO₃, found in limestone, chalk, and many shells. This sparingly soluble salt forms major geological deposits and biological structures.
Cation: A positively charged ion formed by losing electrons or, in some cases, gaining protons. Cations provide the positive component of a salt’s ionic formula.
Neutralization: An acid–base reaction in which acidic and basic properties are reduced, often producing water and a salt. It is a common route to salt formation from acids and bases.
Sodium chloride: The ionic compound NaCl, widely known as table salt and occurring naturally as halite. It is the best-known example of a salt and a major industrial material.
Acid: A substance that donates protons or accepts electron pairs, depending on the acid–base theory used. Acids can form salts, but an acid itself is not necessarily a salt.
Ammonium nitrate: The ionic compound NH₄NO₃, used mainly as a nitrogen fertilizer and also as an energetic material. Its ammonium and nitrate ions illustrate salts made from polyatomic ions.