For 10 points, name this colligative property symbolized pi, the force per unit area across a semipermeable membrane that causes water to flow.
The theta point of a polymer solution can be calculated by expressing this quantity via a virial expansion and setting the second virial coefficient to zero. A reflection coefficient is multiplied by the difference between the interstitial and capillary forms of this quantity in the Starling equation. Changes in this property can be measured using a U-shaped tube whose sides are separated by (*) dialysis tubing. Placing cells in a hypotonic solution will cause them to lyse due to an imbalance in this property. This quantity is equal to molarity times the ideal gas constant times temperature times the van 't Hoff factor. For 10 points, name this colligative property symbolized pi, the force per unit area across a semipermeable membrane that causes water to flow.
The theta point of a polymer solution can be calculated by expressing this quantity via a virial expansion and setting the second virial coefficient to zero.
osmotic pressure [accept oncotic pressure; prompt on pressure]