This equation can be used to find the molar mass of a dissolved substance, and can be derived by equating the free energy on both sides of a semipermeable membrane.  
Although monosaccharides are a more directly usable form of energy storage, considering this property reveals that plants store carbohydrates as polysaccharides to reduce strain on membranes.  The fact that it is equal to the concentration times the universal gas constant times the absolute temperature was discovered by van't Hoff.  This equation can be used to find the molar mass of a dissolved substance, and can be derived by equating the free energy on both sides of a semipermeable membrane.  FTP, name this colligative property which can be measured in atmospheres.
Although monosaccharides are a more directly usable form of energy storage, considering this property reveals that plants store carbohydrates as polysaccharides to reduce strain on membranes.  
osmotic pressure