The Analytical chemistry reference article from the English Wikipedia on 24-Jul-2004
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Analytical chemistry

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Analytical chemistry is the analysis of material samples to gain an understanding of their chemical composition and structure.

Table of contents
1 Types
2 Techniques
3 Methods

Types

Analytical chemistry can be split into two main types:
  1. Qualitative analysis seeks to establish the existence of a given element or compound.
  2. Quantitative analysis seeks to establish the amount of a given element or compound.

Most modern analytical chemistry is quantitative. Quantitative analysis can be further split into different areas of study. The material can be analyzed for the amount of an element or for the amount of an element in a specific chemical species. The latter is of particular interest in biological systems; the molecules of life contain carbon, hydrogen, oxygen, nitrogen, and others, in many complex structures.

Techniques

There are a bewildering array of techniques available to separate, detect and measure chemical compounds.

Methods

Analytical methods rely on scrupulous attention to cleanliness, sample preparation,
accuracy and precision.

Many practitioners will keep all their glassware in acid to prevent contamination, samples will be re-run many times over, and equipment will be washed in specially pure solvents.

A standard method for analysis of concentration involves the creation of a calibration curve.

If the concentration of element or compound in a sample is too high for the detection range of the technique, it can simply be diluted in a pure solvent. If the amount in the sample is below an instrument's range of measurement, the method of addition can be used. In this method a known quantity of the element or compound under study is added, and the difference between the concentration added, and the concentration observed is the amount actually in the sample.


Chemistry
Analytical chemistry | Organic chemistry | Inorganic chemistry | Physical chemistry | Polymer chemistry | Biochemistry | Materials science | Environmental chemistry | Pharmacy | Thermochemistry | Electrochemistry | Nuclear chemistry | Computational chemistry
Periodic table | List of compounds