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Chapter 1: Classification of Analytical Methods Naaimat Muhammed Present day Instrumental Analysis ?Better and Faster ?More Data (Images) ?Miniaturization ?Better data processing methods - Chemo metrics Introduction: Analytical Chemistry deals with methods for determining the chemical composition of samples of matter. A qualitative method yields information about the identity of atomic or molecular species or the functional groups in the sample; a quantitative method, in contrast, provides numerical information as to the relative amount of one or more of these components. Analytical methods are often classified as being either classical or instrumental. This classification is largely historical with classical methods, sometimes called wet-chemical methods, preceding instrumental methods by a century or more. Classical Methods: Separation of analytes by precipitation, extraction, or distillation. Qualitative analysis by reaction of analytes with reagents that yielded products that could be recognized by their colors, boiling or melting points, solubilities, optical activities, or refractive indexes. Quantitative analysis by gravimetric or by titrimetric techniques. In the early years of chemistry, most analyses were carried out by separating components of interest in a sample by precipitation, extraction, or distillation. For quantitative analyses, the separated components were then treated with reagents that yielded products that could be recognized by their colors, boiling points or melting points, their solubility in a series of solvents, their odors, their optical activities, or their refractive indexes. For quantitative analyses, the amount of analyte was determined by gravimetric or by titrimetric measurement. Gravimetric Methods – the mass of the analyte or some compound produced from the analyte was determined. Titrimetric Methods – the volume or mass of a standard reagent required to react completely with the analyte