Popular lines of products used in this technique include the Phenomenex Luna and the Agilent Zorbax, which are partially named in reference to the octadecyl group. Depending on whether the composition of a constituent in this technique changes, its mode is termed “isocratic” or “gradient.” Changing the polarity of substances involved in one form of this technique results in its “reverse-phase” variant. Porous silica gel is used to “pack” the walls of columns in one form of this technique named for being “high-performance.” Pigments can be distinguished in one form of this technique by submerging traces of them placed on cellulose-based paper. For 10 points, name this technique that dissolves a mixture in a mobile phase before moving it through a stationary phase to separate its components. ■END■
ANSWER: chromatography [accept (reverse-phase) high-performance liquid chromatography or high-pressure liquid chromatography or HPLC; accept paper chromatography or PC; accept column chromatography or CC; prompt on elution by asking “which occurs during what technique?”] (The first line refers to C18 columns sold for use in HPLC.)
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= Average correct buzz position