A flash purification system using prepacked cartridges containing different silica weights and particle sizes was employed to demonstrate the influence of column characteristics on chromatographic resolution. This chromatographic experiment was a helpful introduction to chromatographic courses where the influence of particle sizes was addressed only theoretically, and it allows students to experience the concept in an active learning style experiment. After running a predefined set of experiments to understand concepts, students were asked to design their own experiment to achieve the best chromatographic resolution. Moreover, the difference of mass versus concentration detectors was highlighted using an ultraviolet (UV) detector and an evaporative light scattering detector (ELSD). Questionnaires were also used to define the students' initial knowledge and to assess what they learned following this lab.