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0 pointskgwgk3y ago0 comments

I don't understand the answer. (Assuming it's "yes".)

What is the explanation of why they will mix? Does it involve probabilities?

Why didn't you say "I have no way of knowing. It depends on the positions and velocities of each of the molecules and they will either mix or they won't."

(By the way, if I had asked about a container of neon and a container of helium would you have also claimed that asking whether they will mix is a chemistry question?)

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2 comments · 1 top-level

ThomPete3y ago· 1 in thread

The explanation of how different molecules combine when mixed.

Has nothing to do with probability.

If you can predict that it happens exactly 10% of the time (ex. every 10th time) then you have an explanatory model that can explain why that is and you don't need statistics.

I don't think you are asking what you think you are asking.

kgwgkOP3y ago

What I'm asking is a quite simple physics question. I know what I'm asking - what I don't know is why you don't at least try to give a definite answer. I'm trying to make it clearer (let me know if it's not clear enough):

I have a container with two compartments, separated by a moving wall. In each side there is an equal volume of gas at normal temperature and pressure (helium and neon). What happens when the moving wall is removed?

A) The gases will mix.

B) The gases will not mix.

C) I have no way of knowing. It depends on the positions and velocities of each of the particles and they will either mix or they won't.

The usual (wrong?) answer is A. But it seems that you could (should?) answer C. Because you cannot rule out the possibility that they don't mix - you would be guessing.

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