Osmotic pressure

Definition

Osmotic pressure is the pressure required to prevent the flow of a solvent into a solution through a semipermeable membrane. It is a colligative property dependent on the concentration of solute particles.

5 Must Know Facts For Your Next Test

1. Osmotic pressure can be calculated using the formula $\Pi = iMRT$, where $\Pi$ is osmotic pressure, $i$ is the van't Hoff factor, $M$ is molarity, $R$ is the gas constant, and $T$ is temperature in Kelvin.
2. It plays a crucial role in biological systems such as maintaining cell turgor pressure and kidney function.
3. Higher solute concentration leads to higher osmotic pressure.
4. The concept of osmotic pressure helps explain phenomena such as osmosis and dialysis.
5. Osmotic pressure can influence fluid movement across cell membranes, affecting processes like nutrient absorption and waste removal.

Review Questions

• What role does osmotic pressure play in biological systems?
• How does an increase in solute concentration affect osmotic pressure?
• Write down the formula for calculating osmotic pressure and define each variable.

Related terms

Diffusion:

The movement of particles from an area of high concentration to an area of low concentration until equilibrium is reached.

Osmosis:

The diffusion of water across a semipermeable membrane from an area of low solute concentration to an area of high solute concentration.

Semipermeable Membrane:

A barrier that allows certain molecules or ions to pass through it by diffusion and occasionally specialized facilitated diffusion.