Define the Problem Carefully

Exactly what is the analytical problem and what is the minimum analytical information needed to provide a reasonable answer In this connection it is well to categorize the type of analysis desired oxyhahdes in drinking water, arsenic spe-ciation in drinking water, speciation of chromium in plating baths, etc. 

The second step is to describe the expected sample composition as completely as possible. For oxyhalide analysis, it is good to know which oxyhalide species are 

Ion Chromatography, 4th Ed. James S. Fritz and Douglas T. Gjerde Copyright 2009 WILEY-VCH Verlag GmbH Co. KGaA, Weinheim ISBN 978-3-527-32052-3 

The next step is to consult the literature for information. Useful sources include books and standard methods from sources such as EPA, AOAC and ASTM, company literature, and journal articles. It is likely that other workers have faced situations similar or even identical to the problem at hand. It is interesting to note that difficult problems frequently gamer more publications than easier problems. At this point, it should be possible to select an analytical method. The method selected is likely to reflect the personnel and equipment available and the worker s own preferences. The method selected need not be ideal a method that simply works is sufficient. It is also necessary to consider any modifications needed to apply the selected method to your own analytical problem. 

The final step is to confirm that the modified analytical method works for your particular situation. Does the resolution of peaks, sensitivity and reproducibility meet your requirements Correct identification of each analytical peak is essential. 

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