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.
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