PH BUFFER Meaning and
Definition
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A pH buffer, also known as a hydrogen-ion buffer, refers to a solution or substance that is used to resist or maintain a stable pH (acidity or alkalinity) level when additional acidic or basic substances are introduced. It acts as a chemical sponge, absorbing or releasing hydrogen ions (H+) to neutralize any changes in pH.
The primary purpose of a pH buffer is to keep the pH within a specific range, preventing extreme fluctuations that could otherwise be harmful to biological systems or chemical reactions. It ensures that a particular environment, such as a laboratory or a living organism, maintains an optimal pH level for normal functioning.
A pH buffer consists of a weak acid and its corresponding conjugate base or a weak base with its conjugate acid. The choice of buffer components depends on the desired pH range. When an acid is added to the buffer solution, the conjugate base of the weak acid reacts with the added hydrogen ions, counteracting the increase in acidity and maintaining the pH. Similarly, when a base is added, the weak acid component of the buffer reacts with the hydroxide ions, preventing excessive alkalinity.
Commonly used pH buffer systems include phosphate buffer (pH range of 5.8-8.0), acetate buffer (pH range of 3.7-5.6), and bicarbonate buffer (pH range of 9.2-10.4). pH buffers find applications in various scientific fields, including biological and biochemical experiments, medical diagnostics, environmental monitoring, and quality control in industries such as pharmaceuticals and food production.
Etymology of PH BUFFER
The word "pH buffer" does not have a direct etymology as it is made up of two separate terms: "pH" and "buffer".
- "pH" stands for "power of hydrogen" or "potential of hydrogen". It is a measure of the acidity or alkalinity of a solution. The term was coined by Danish biochemist Søren Peder Lauritz Sørensen in 1909. The "p" refers to the negative logarithm and the "H" refers to the concentration of hydrogen ions.
- "Buffer" is derived from the Old High German word "buohhan" and the Middle English word "buffe" or "buffer", both meaning "to cushion" or "to muffle". In chemistry, a buffer refers to a solution that resists changes in pH when an acid or a base is added.
