Therefore, to analyze the standards before so knew where and when the peak analysis of samples, they will know that there is that type of substance or not, by comparing the retention time with standard substance.
Therefore, it must be analyzed in order to know the position of the peak and when samples will know that the substance is or not by comparing the retention time with standards.
So it must be analyzed to know the location of the standard peak when analyzing samples will know that there are species that or not by comparing the value. Retention time with standard compounds