Sulphur-bearing species column densities as a time function (gas phase) for the hot core Model 5 with a star mass of 10 M_⊙, f_r = 0.85, and 0.1 S_⊙ sulphur abundance. The points indicate the observational results of SO, SO₂, CS, OCS, H₂CS, and H₂S. In this case,  S⁺ freezes out to form OCS (50%) and H₂S (50%) on the mantles at the end of Phase I.