Osmosis – dependence of the osmotic pressure on the concentration

Principle

Osmosis describes the phenomenon that solvent molecules move through a partially permeable membrane into a region of higher solute concentration. Thus, the concentration of solute is equalized on both sides. The experimental set-up consists of seven chambers that are filled with solutions of sugar with different concentrations. The liquid column in the capillaries is determined and the dependence of the osmotic pressure on the concentration can easily be shown.

Benefits

• Quantitative determination of the osmosis processes
• Multiple measurement points permit detailed analysis
• Scalable experiment: number of measurement points can be varied

Tasks

1. Investigate the phenomenom of osmosis in a simple model experiment.
2. Determine the dependence of osmotic pressure on concentration of dissolved molecules.

Learning objectives

• Osmosis
• Osmotic pressure
• Concentration