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1. Introduction          2. Learning objectives     3. History 

4. Basic Principles    5. Detection Methods      6. Chromatograms

7. Instrumentation    8. Experiments                9. Troubleshooting
   

Chromatograms
 

 The time to elute an analyte is a function of how long the analyte is retained on the column, therefore the output of IC is a graph of conductivity as a function of time, called a chromatogram.  Based on the previous discussion of elution, you may expect a chromatogram to look something like:
 
mock chromatogram showing elution of square before elution of circle
 
However, we need to consider another process that impacts shape of the elution peaks.  As an analyte flows through the column, some of the analyte molecules may pass by through the length of the stationary phase faster or slower than would be expected due to diffusion processes or the formation of channels.  An example of this can be seen in the figure with the path of each ion shown in the figure. 
two paths of flow through a IC column  

 

 
 
  If the two ions are traveling at the same speed, set by the flow of the eluent, what can you say about when they will emerge?  Will they emerge at the same time?  (continue when answered)
 
 
 
 
 
 
 
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