bufferlahustega

Buffer solutions, also known as bufferlahustega in Estonian, are aqueous solutions that resist changes in pH upon the addition of an acid or base. They are crucial in many chemical and biological processes where maintaining a stable pH is essential. A buffer solution typically consists of a weak acid and its conjugate base, or a weak base and its conjugate acid. The common species in the buffer system are present in relatively high concentrations, allowing them to neutralize small amounts of added acid or base.

The principle behind buffer action lies in the equilibrium established between the weak acid (HA) and its conjugate base (A⁻): HA ⇌ H⁺ + A⁻. If a strong acid is added, the conjugate base A⁻ reacts with the excess H⁺ ions to form the weak acid HA, thus minimizing the increase in H⁺ concentration. Conversely, if a strong base is added, the weak acid HA reacts with the hydroxide ions (OH⁻) to form water and the conjugate base A⁻, thereby minimizing the decrease in H⁺ concentration.

The effectiveness of a buffer solution is described by its buffer capacity, which is the amount of acid or base that can be added to a given volume of the buffer solution before the pH changes significantly. Buffer capacity is maximized when the concentrations of the weak acid and its conjugate base are equal, which occurs at a pH equal to the pKa of the weak acid. Buffer solutions are widely used in analytical chemistry, biochemistry, and industrial processes to control pH in reactions and to maintain the stability of sensitive substances.