Acidbased

Acid-based chemistry, commonly referred to as acid-base chemistry, concerns systems in which acids and bases interact and exchange protons or electron pairs. The concept originated with the Arrhenius definition, which characterizes acids as substances that increase hydrogen ion concentration in water and bases as substances that increase hydroxide concentration. Bronsted and Lowry broadened the view to proton donors and acceptors, while Lewis framed acids as electron-pair acceptors and bases as donors. These models are complementary and apply in different contexts, including non-aqueous solutions and gas-phase reactions.

Key concepts include the pH scale, potentiometric and spectroscopic measures of acidity, and pKa, which indicates acid strength in a given context. Buffers resist changes in pH by balancing added acid or base. Neutralization reactions, in which an acid and base form a salt and water, are fundamental examples: HCl + NaOH forms NaCl and H2O.

Typical acids include hydrochloric acid and acetic acid; bases include ammonia and sodium hydroxide. The field extends to biology, where body fluids rely on buffering systems such as bicarbonate and phosphate to maintain pH homeostasis, and to environmental science, where soil and water chemistry are influenced by acidity.

Applications span chemical synthesis, medicine, food science, and industrial processes. Safety considerations emphasize corrosivity and appropriate handling of strong acids and bases, including the use of personal protective equipment and proper waste disposal.

See also: acid, base, pH, buffer, neutralization, acid-base theory.