Analytical Chemistry

Analytical Chemistry is the subdivision of chemistry concerned with identification of materials (qualitative analysis) and with determination of the percentage composition of mixtures or the constituents of a pure compound (quantitative analysis). The gravimetric and volumetric (or "wet") methods (precipitation, titration and solvent extraction) are still used for routine work and new titration methods have been introduced e.g. cryoscopic, pressure-metric (for reactions the produce a gaseous product), redox methods, and use of a F-sensitive electrode etc. However, faster and more accurate techniques (collectively called instrumental) have been developed in the last few decades. Among these are infrared, ultraviolet, and x-ray spectroscopy where the presence and amount of a metallic element is indicated by lines in it's emission or absorption spectrum... colorimetry by which the percentage of a substance in soluble is determined by the intensity of it's colour... chromatography of various types by which the components of a liquid or gaseous mixture are determined by passing it through a column of porous material or on thin layers of finely divided solids... separation of mixtures in ion exchange columns and radioactive tracer analysis. Optical and electron microscopy, mass spectrometry, microanalysis, Nuclear Magnetic Resonance (NMR) and Nuclear Quadrupole Resonance (NQR) spectroscopy all fall within the area of analytical chemistry. New and highly sophisticated techniques have been introduced in recent years, in many cases replacing traditional methods.