This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Body Fluids, Subject name: Physiology
Osmotic pressure of 1 mol of ideal solute relative to pure water is: (PGI June 2009) 
Select and explain. 
A. 6.5 atm., B. 22.4 atm., C. 4 atm., D. 2 atm.
B: 22.4 atm.
Answer: B: 22.4 atm. 
Explanation: Ans : B (22.4 atm.) "1 mol of an ideal solute dissolved in l000g of water (a 1 m or molal solution) at 1 atm pressure yields a solution whose osmotic pressure relative to pure water is 22.4 atm (at25degC)"- Biochemistry by Reginald H. Garrett 3rd/37Osmotic PressureOsmose's the diffusion of water through a semi-permeable membrane. More specifically, it is the movement of water across a semi-permeable membrane from an area of high water potential (low solute concentration) to an area of low water potential (high solute concentration).It is a physical process in which a solvent moves, without input of energy, across a semi-permeable membrane (permeable to the solvent, but not the solute) separating two solutions of different concentrations. Osmosis releases energy, and can be made to do work, as when a growing tree root splits a stoneThe force per unit area, or pressure, required to prevent the passage of water through a selectively permeable membrane and into a solution of greater concentration is equivalent to the osmotic pressure of the solution, or turgor. Osmotic pressure is a colligative property, meaning that the property depends on the concentration of the solute but not on the type of solute.