Molarity from Osmotic Pressure Calculator for Solutions | Determine M Using π, T & i
Use osmotic pressure measurements to determine the molarity of a solution. Account for temperature and solute particle effects to obtain the corresponding molar concentration.
About Molarity from Osmotic Pressure Calculator
Osmotic pressure offers an interesting way to find the concentration of a solution without directly measuring how much solute is present. When a solution is separated from a pure solvent by a semipermeable membrane, the dissolved particles create a pressure associated with the movement of solvent.
The Molarity from Osmotic Pressure Calculator uses the relationship π = iMRT to work backward from osmotic pressure to molarity. Here, π represents osmotic pressure, i is the van’t Hoff factor, M is molarity, R is the gas constant, and T must be expressed in kelvin.
This calculation is useful in physical chemistry, laboratory experiments, biological studies, and colligative-property problems. It can also be helpful when determining the approximate molar concentration of an unknown solution from experimental osmotic pressure data.
One detail deserves special attention: temperature must be converted to absolute temperature before using the equation. The van’t Hoff factor also needs to reflect how the solute behaves in solution. For a non-electrolyte that does not dissociate, i is approximately 1 under ideal conditions.