Final answer:
A solvent front is the furthest point reached by the solvent on the chromatography paper or plate during a chromatographic run, used to calculate retention factors for component identification.
Step-by-step explanation:
The term solvent front refers to the line or edge that forms in chromatography techniques, marking the furthest point reached by the solvent on the chromatography paper or plate. During a chromatographic run, the solvent moves along with the sample, carrying the different components at various speeds based on their affinity towards the solvent (mobile phase) and the stationary phase, often a chromatography paper or solid surface. The solvent front is important because it is used as a reference point for calculating the retention factor (Rf) values for each component, which helps in identifying them.