Why are buffers needed

Many biological and chemical systems involve acid-base equilibria and therefore depend critically on the pH of the solution. An example is the extent to which the viability and growth of organisms and tissues depends on the pH of the cell fluids and of the media in which the cells grow (Albert, 1968). 

The effectiveness of many chemical separations and the rates of many chemical reactions are governed by the pH of the solution. Buffer solutions offer advantages for controlling reaction conditions and yields in organic syntheses. The objection that this adds material which must later be removed is less serious if volatile buffers are used. A particularly promising field in this respect is biomimetic chemistry (Breslow, 1972) which attempts to imitate natural reactions and enzymic processes as a way to improve the power of organic chemistry. 

In analytical and industrial chemistry, adequate pH control may be essential in determining the courses of precipitation reactions and of the electrodeposition of metals. Physicochemical studies of reaction kinetics and chemical equilibria often require solutions to be maintained at a definite pH value. Buffers are needed for pH standardization and control in the research laboratory, the factory and the medical clinic. For kinetic, equilibrium and physiological studies it is often desirable to make measurements over a controlled range of pH values while, at the same time, maintaining constant ionic strength in the medium. 

Much of the success of complexometric methods of chemical analysis depends on the use of buffers to maintain pH constancy so that small changes in free metal ion concentrations can be detected by suitable metallochromic indicators. 

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