[bruno golik]

Greetings
i have a question about osmotic pressure between 2 solutions (in the beginning both have something soluted in them,but at different concentratons). let us take a case of an U tube with NaCl soluted on both sides. at the start both of them have the same height of solution columns ,but due to osmosis the hights will change.

i know that the formula π=icRT (c is the molar concentration of the solute) defines the osmotic pressure of a certain solution,and in the case when in the U tube there is a solution on one side and pure water on the other,the solution pillar would rise so that ρgΔh=icRT. my question is:if we want to calculate the difference in the water pillars between 2 solutions,are we allowed to just write that the difference in hydrostatic pressure is a difference in their osmotic pressures,like ρgΔh=iRT*(c1-c2) where c1 and c2 are their respective concentrations?