INSTRUMENTAL METHODS OF CHEMICAL ANALYSIS

Analytical chemistry may be defined as the science and art of determining the composition of materials in terms of the elements or compounds contained in them. Historically, the development of analytical methods has followed closely the introduction of new measuring instruments. The first quantitative analyses were gravimetric, made possible by the invention of a precise balance. In the closing decades of the nineteenth century, the invention of the spectroscope brought with it an analytical approach that proved to be extremely fruitful. At first it could be applied only qualitatively, gravimetric and volumetric methods remaining for many years the only quantitative procedures available. Gradually a few colorimetric and turbidimetric methods were introduced. Then it was found that electrical measurements could be used to advantage to detect end points in titrations. Since about 1930, the rapid development of electronics has resulted in a major revolution in analytical instrumentation. Today the chemist, whether he calls himself an analytical specialist or not, must have a working knowledge of a dozen or so instrumental methods virtually unknown a generation ago.