Elemental Analysis of Organics

A systematic difference is found, supported by indirect evidence that from experience precludes any explanation other than effect observed. This case does not necessarily call for a statistical evaluation, but an example will nonetheless be provided in the elemental analysis of organic chemicals (CHN analysis) reproducibilities of 0.2 to 0.3% are routine (for a mean of 38.4 wt-% C, for example, this gives a true value within the bounds 38.0. .. 38.8 wt-% for 95% probability). It is not out of the ordinary that traces of the solvent used in the... 

Hausler D. (1987) Trace element analysis of organic solutions using ICP mass spectrometry, Spectrochim Acta, Part B 42 63-73. 

When based on GC, the elemental analysis of organic compounds normally consists of the following steps (1) the preparation and introduction of a sample into the instrument (2) chemical conversion of the sample into simple volatile products (3) chromatographic separation of these products (4) detection of the separated products and quantitative processing of the results. 

Hausler, D., Trace Element Analysis of Organic Solutions Using Inductively Coupled Plasma-Mass Spectrometry, Spectrochimica Acta Part B, Vol. 42, 1987, pp. 63-73. 

Berzelius was the lirst to determine the atomic mass of the elements with satisfactory accuracy. It was he who introduced the chemical symbols still in use. His dualistic electrochemical hypothesis concerning the structure of compounds was a fundamental and progressive chemical theory for a long period. He was one of the pioneers of elemental analysis of organic substances. Berzelius wrote numerous books. His manual of chemistry has been translated into several languages and was reprinted five times in Berzelius s lifetime. In his annual reports, entitled Jahresbericht, published from 1821 until his death he critically abstracted the scientific publications of the year. The Jahresbericht was the ancestor of the numerous present scientific abstracting publications, all of them can be traced back to it. Besides cerium Berzelius discovered... 

In the early history of chemistry, all chemists found themselves performing analyses of one kind or another. In more recent times, analytical procedures have become much more sophisticated, and analytical chemistry has in consequence become a specialised branch of the subject. The skills of the analyst are now utilised not only by other chemists, but also by those carrying out investigations in fields such as forensic science, environmental science and the quality control of all manner of products. Some analytical techniques (for example the quantitative elemental analysis of organic compounds and the investigation of molecular structure by physical methods) have been considered in earlier chapters. 

The quantitative elemental analysis of organic compounds, perfected by Liebig for carbon and hydrogen in 1831 and by Dumas for nitrogen in 1834, has been described in Chapter 8. An alternative method for the determination of nitrogen was devised in 1883 by Johan Kjeldahl (1849-1900) in which the element is converted to ammonia, which is then determined by titration. The standard... 

Kawasaki, A., and Arai, S. (1996). Evaluation of digestion methods for multi-elemental analysis of organic wastes by inductively coupled plasma mass spectrometry. Soil Sci. Plant Nutr. 42(2), 251. 

The general principle of elemental analysis of organic compounds involves the total breakdown (decomposition) of the organic molecules so that the individual elements are converted into their respective elemental forms or simple inorganic compounds. So that the objective of quantitative analysis can be accomplished, two conditions must be met (1) the decomposition of the sample should be complete and (2) the element to be determined should be transformed into one specific product that can be measured accurately. 

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