Diffusion - Cambridge IGCSE Chemistry 0620


Diffusion is the free movement of particles of matter freely in all directions due to random motion


as we discussed earlier the movement of particles in all states of matter and the space between particles and movement speed  we can see how these particles can move in between other phase or in the same phase


like can the particles of one gas move freely in between the particles of another gas , or even in between liquid particles

we can see how NO₂ molecules can diffuse in between the components of air .
or how can a fizzy drink have the particles of CO₂ gas move freely in between the water molecules 

since the movement of particles of gases is less restricted than those in solid or liquid states;Diffusion is more common to happen in the gas particles among other gas or among liquid state 

The liquid particles can also diffuse in between other liquid or in gasif you spray water in the air you can see how liquid particles of water can move freely in between air particles

and also ethanol molecules can spread and diffuse in between water molecules


and also the solid particles in between a liquid or in a gas

In case of solid particles since there is no space between particles it is impossible for any type of phase to diffuse between them .
Diffusion of gases is quick because the particles of a gas move quickly. It happens even faster in hot gases.

so we can define 

Diffusion 

as : the free movement of particles of matter freely in all directions in between other particles 


Because of the continuous motion which is irregular and random the particles can start moving (diffuse) from one place to another 

The speed of this motion depends on some factors , the most important of which is the mass of the moving particles

The higher the mass of the particles the slower is the motion and vice versa

as we can see in the following experiment






Check also



Where to go from here 

CIE IGCSE Chemistry 

Cambridge Chapter 1





Chapter 1 All Resources



IGCSE 0620 All Resources

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