Compression copy In solids particles are very close

Compression (copy) • In solids, particles are very close together already meaning that it isn’t possible to squeeze them any closer • In liquids, particles are close together with hardly any space between them- difficult to get particles any closer • In gases, the particles are far apart with lots of space between them- it is easier to squeeze them together.

Learning Intention • To learn about diffusion

Diffusion Demo • Stand in 5 rows • Close your eyes • Raise your hand when you can smell the perfume

Think, Pair, Share Think of the particles- can you explain why this happens? Think: 30 seconds think time- no speaking Pair: Person 1 has 30 seconds to speak while their partner listens and vice versa. You then have 1 minute to discuss and come up with a joint answer Share: Share your ideas with the rest of the class

Diffusion Experiments • Place one crystal in a beaker of water and watch what happens

Diffusion • Particles spread to fill all AVAILABLE SPACES • Particles move from an area of lots of particles (HIGH CONCENTRATION) to an area with fewer particles (LOW CONCENTRATION)

Diffusion of gases • Smells travel • Smell strongest the closer you are (high concentration) • Get weaker further away you are

Diffusion (copy) • Diffusion is the movement of molecules from where there’s A LOT to where there’s NOT. • Particles spread out to fill available spaces. • An example of diffusion is the smell of a fart spreading round a classroom.