Internally yes they probably convert but it is not exposed anywhere, kind of like Chemical reaction you convert everything to Mols internally to do the calculat

Internally yes they probably convert but it is not exposed anywhere, kind of like Chemical reaction you convert everything to Mols internally to do the calculations but externally you report all of the inputs as a mass. The control system won't tell the operator to add an extra 0.3 mols of reactant or to tilt the furnace by Pi/4 radians