Final answer:
Osmotic pressure is the pressure required to stop osmosis, the movement of solvent through a semipermeable membrane from a lower to a higher solute concentration. It can be calculated using the formula Π = MRT. The pressure is proportional to solute concentration and is greater for electrolytes like NaCl compared glucose.
Step-by-step explanation:
Osmotic Pressure
Osmotic pressure is a colligative property that is measured when a semipermeable membrane separates two solutions of different solute concentrations. It refers to the pressure needed to prevent the flow of a solvent through the membrane, from the area of lower solute concentration to the area of higher solute concentration. In essence, osmotic pressure compels the solvent to move across the barrier, balancing the solute concentrations on both sides.
The osmotic pressure, often symbolized as Π (Greek letter Pi), can be calculated using the formula Π = MRT, where 'M' represents the molarity of the solution, 'R' is the ideal gas constant (0.08206 L atm/mol K), and 'T' is the temperature in Kelvin.
For example, the osmotic pressure of a 0.333 M glucose (C6H12O6) solution at 25°C (which is 298 K when converted to Kelvin) is found by plugging these values into the formula. This will show that osmotic pressure is proportional to the solute concentration.
With ionic compounds like NaCl, which disassociate into two ions, the effect on osmotic pressure is greater than that of non-electrolytes like glucose, which do not dissociate in solution. As a result, osmotic pressure is directly proportional to the number of solute particles present in the solution.