Each analyte partitions between the mobile phase (flowing solvent)
and the stationary phase packed in the column; the more strongly it
adsorbs, the slower it travels. As bands reach the end of the column
they pass the detector and appear as peaks on the chromatogram trace
at the bottom — their spacing in time is what analytical chemists
use to identify and quantify each compound.
k' = (tR − t0) / t0 (retention factor)
N = 16 (tR / w)^2 (theoretical plate number)
Rs = 2(tR2 − tR1) / (w1 + w2) (resolution between peaks)
- Mobile phase strength — a stronger (more elution-power) mobile phase speeds every analyte through the column, reducing retention time.
- Column length — a longer column gives more theoretical plates N, sharpening bands and improving resolution between close peaks.
- Detector wavelength — each analyte absorbs light differently at a given wavelength; tuning it changes which peaks show up strongly.
- Sample mixture — simple (2 analytes) or complex (4 analytes) presets, each with different intrinsic retention factors.
This mirrors real HPLC/GC method development: analysts trade off
mobile-phase strength, column length and detection wavelength to get
clean, well-resolved peaks in the shortest possible run time.