Why do gases exert pressure?

Question

Accepted Answer

Welcome back everyone in this example. We need to explain the reasons why gasses apply pressure. So what we're going to visualize is a balloon and we want to recall that balloons are made up of helium gas and helium is not a di atomic gas, it's just a single atom of helium which makes up the molecule. So it's mon atomic gas. And considering these gas or these helium gas molecules in our balloon, we want to recall that gas molecules are random, so they're going to be randomly spread out. They have a high amount of entropy recall that entropy is represented by the simple S and it speaks to the disorder of our molecules. So because of this disorder, there's a lot of empty space and randomly scattered helium molecules throughout the balloon that we're visualizing here. And these helium molecules are just randomly moving throughout the space of the balloon here. And so we can say that the random motion of our helium gas molecules in the balloon exert pressure on the walls of the balloon. So this pressure is called caused by the collisions of these helium molecules on the walls of this balloon here. So to finalize this example, we're going to say that therefore gasses apply pressure due to their randomly moving particles colliding with their containers walls. And this makes sense because we would recall that gasses will typically have higher entropy ease than solids or liquids since they have such random motion and disordered movement. So for our final answer, we are going to confirm this statement here highlighted in yellow, I hope everything I explained was clear. If you have any questions, please leave them down below, and I will see everyone in the next practice video.

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