Unformal question about molecules of gases

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Gas molecules move chaotically, which affects their diffusion rate and explains why it takes time for scents, like perfume, to reach a person standing two meters away. Wind is generated by pressure and temperature differences, not solely by the speed of individual gas molecules. The collective movement of countless particles results in slower wind speeds compared to the rapid motion of individual molecules. Understanding these principles clarifies why scents disperse gradually and why wind isn't consistently fast. Overall, the behavior of gas molecules is influenced by their interactions and environmental conditions.
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In high school I've been told that the molecules of gases have generally speed of severals kilometers per second. Hence why the wind is not always present, and why not that fast? (I guess it has to see with the huge number of particles... I never studied such a system in Physics yet, I believe but I might be wrong.)
Also why when I open a bottle of perfume I cannot smell its odor if I'm at say 2 meters from it? (It's like the big molecules of perfume cannot move that fast at all since there are too much other molecules or so).
Thanks.
P.S.: I've asked this question to my teacher when I was younger and it seems he misunderstood the question. Answering that the wind was a depression or something like that. Which do not say why the wind is not as fast as most molecules in air so most molecules forming the wind itself.
 
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fluidistic said:
In high school I've been told that the molecules of gases have generally speed of severals kilometers per second. Hence why the wind is not always present, and why not that fast? (I guess it has to see with the huge number of particles... I never studied such a system in Physics yet, I believe but I might be wrong.)
Also why when I open a bottle of perfume I cannot smell its odor if I'm at say 2 meters from it? (It's like the big molecules of perfume cannot move that fast at all since there are too much other molecules or so).
Thanks.
P.S.: I've asked this question to my teacher when I was younger and it seems he misunderstood the question. Answering that the wind was a depression or something like that. Which do not say why the wind is not as fast as most molecules in air so most molecules forming the wind itself.

Essentially, the gas molecules are moving in a chaotic pattern so it takes longer for them (e.g. "perfume molecules") to diffuse through the air and to your nose.

Wind develops as a result of pressure or temperature differences between two locations on the Earth's surface.

CS
 
Thank you stewartcs, I get it.
 
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