The key difference between RP HPLC and HIC is that RP HPLC uses a more polar mobile phase and a less polar stationary phase. Whereas, HIC uses a hydrophobic stationary phase that allows the hydrophobic molecules to attach to it.
Chromatography is an analytical technique that helps to separate a mixture into its components. First, we have to dissolve the sample to be separated into a solution. This solution-substance mixture is called the mobile phase. Then the mobile phase is passed through another material called the stationary phase. The stationary phase determines the separation of the components. The separation occurs due to the partitioning of material between the mobile phase and the stationary phase.