The molecules are continually colliding with each other and with the walls of the container. When a molecule collides with the wall, they exert<span> small force on the wall The </span>pressure exerted<span> by the </span>gas<span> is due to the sum of all these collision forces.The more particles that hit the walls, the higher the </span>pressure<span>.</span>
Looks like you need to review through the lesson and take notes as it tells you in the lesson what each of these are.
C. 90 m
30m per second... and it takes 3 seconds
3x30= 90
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