119. Solving a chemistry problem

Solutions of sodium dodecyl sulfate were studied by osmometry at 40°C. A surfactant solution with a concentration equal to sCMC was placed into the osmometer chamber intended for the solvent. Solutions of surfactants with a variable concentration c exceeding the cCMC by cM (surfactant concentration per micelle fraction) were placed in the chamber intended for the test solution. The osmometer membrane was chosen such that neither micelles nor molecularly dispersed surfactant passed through. Below are the results obtained in the presence of 0.2 mol/l NaCl:
cm, kg/m3 30 40 50 60
, Pa 3124 4476 5973 7648