Final answer:
The control of weak liquor flow to the absorber is related to osmotic pressure, which occurs during osmosis and is calculated with the equation Π = MRT.
Step-by-step explanation:
The flow of weak liquor to the absorber is not directly controlled by the pressure of the strong liquor pump. Instead, the control typically relates to the osmotic pressure which is generated during the process of osmosis. Osmosis causes a net flow of solvent, such as water, through a semipermeable membrane due to different solute concentrations on each side. In an osmotic system, as the volume of the solution increases, the hydrostatic pressure also increases due to the weight of the solution's column.
When this pressure, known as the osmotic pressure, reaches a certain point where it can counteract the flow rate of osmosis, solvent transfer stops. This osmotic pressure can be calculated for dilute solutions using the equation Π = MRT, where Π represents the osmotic pressure, M is the molarity of the solute in the solution, R is the gas constant, and T is the absolute temperature.