Page 53 - York Global Science 6 - Physical Science
P. 53
Physical Science
Let’s Learn
Diffusion is the movement of particles from an area of high concentration
to an area of low concentration. When there are different areas of high and
low concentration, there is a concentration gradient.
low high
concentration concentration
concentration gradient
Different particles mix together because of diffusion.
Diffusion happens in liquids and gases because of the random movement
of particles. The particles collide, change direction and mix together. After
diffusion happens, the particles are mixed so that they have the same
concentration everywhere and there is no concentration gradient.
no concentration gradient
Smells travel by diffusion. We can smell food, perfume and other things
because the particles travel through the air by diffusion.
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