Analyte (virtual solution)
Add species and concentrations. Volume is fixed (e.g. 50 mL).
Titrant
Concentration and pKa of the titrant (for bases use conjugate-acid pKa = 14 − pKb). Acid vs base inferred from pKa (first < 7 = acid; ≥ 7 or empty = base).
Titration curve
pH vs titrant volume. Recalculated when analyte or titrant changes.