Diffusion

Let’s learn

Core knowledge: Diffusion is the net movement of particles from higher to lower concentration due to random particle motion.

Explain diffusion and predict how factors affect its rate.

See it

Oxygen concentration is higher in alveolar air than in deoxygenated blood, so oxygen diffuses into the blood across the thin alveolar wall.

Try it together

Model random movement with counters while maintaining more particles on one side initially.

Now you try

1. Define diffusion. 2. Explain why higher temperature increases rate. 3. Give one diffusion example in cells.