Is this a eureka moment? .how do we know atoms exist?

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just picture what happens when you fill a 2 liter soda bottle with water (or any liquid) and try to pour it all out at once. it comes out in clumps. This means there will be competition, since all the water will try to escape all at once. the fact that there is competition means that there must be more than one seperate entity competing. if there were no spaces between the atoms, the water would all flow out uniformly and consistently. and I suspect, - maybe - , that the time intervals between clumps can be measured by avocadro's number and, in turn, can MEASURE avocadro's number.

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The separate entity competing is just air trying to get in to the bottle to replace the liquid which drained out.
The rate at which it does so will be related to the diameter of the drain hole amongst other factors, such as the viscosity of the fluid.

davenn
SteamKing
Staff Emeritus
Homework Helper
just picture what happens when you fill a 2 liter soda bottle with water (or any liquid) and try to pour it all out at once. it comes out in clumps. This means there will be competition, since all the water will try to escape all at once. the fact that there is competition means that there must be more than one seperate entity competing. if there were no spaces between the atoms, the water would all flow out uniformly and consistently. and I suspect, - maybe - , that the time intervals between clumps can be measured by avocadro's number and, in turn, can MEASURE avocadro's number.

davidbenari
just picture what happens when you fill a 2 liter soda bottle with water (or any liquid) and try to pour it all out at once. it comes out in clumps. This means there will be competition, since all the water will try to escape all at once. the fact that there is competition means that there must be more than one seperate entity competing. if there were no spaces between the atoms, the water would all flow out uniformly and consistently. and I suspect, - maybe - , that the time intervals between clumps can be measured by avocadro's number and, in turn, can MEASURE avocadro's number.
that's not correct

my explanation is still valid

DrClaude
Mentor
You can fully study and understand this kind of fluid dynamics without referencing the existence of atoms. It is not a proof of the existence of atoms.

you still didn't answer the question. why doesn't the air push all the liquid out in a uniform flow?

You can fully study and understand this kind of fluid dynamics without referencing the existence of atoms. It is not a proof of the existence of atoms.
just tell me why my explanation is wrong

DrClaude
Mentor
you still didn't answer the question. why doesn't the air push all the liquid out in a uniform flow?
The air doesn't push the liquid out. The liquid is being pulled out by gravity and air must full the low pressure volume left by the moving liquid for the liquid to continue to pour out.

if there were no spaces between the atoms, the water would all flow out uniformly and consistently.
Why?

just tell me why my explanation is wrong[/
The air doesn't push the liquid out. The liquid is being pulled out by gravity and air must full the low pressure volume left by the moving liquid for the liquid to continue to pour out.

Why?
ok. I never said that gravity doesn't pull the water out. why doesn't gravity pull the water out uniformly and consistently?

why can't you just admit that this is a eureka moment?

What?, you have discovered that pouring liquid out of a bottle results in a bottle full of air?

DrClaude
Mentor
why doesn't gravity pull the water out uniformly and consistently?
Because then air couldn't get in to fill the void being created.

why can't you just admit that this is a eureka moment?
This site is for discussing science. Your "eureka moment" is in no way a demonstation of the existence of atoms.

Because then air couldn't get in to fill the void being created.

This site is for discussing science. Your "eureka moment" is in no way a demonstation of the existence of atoms.
give me a valid explanation for why it's not a demonstration for the existence of atoms. you can't just say it without an explanation.

What?, you have discovered that pouring liquid out of a bottle results in a bottle full of air?
that sarcastic comment didn't answer anything. I know that air fills the bottle as the water is pouring out. why does the water come out in clumps?

give me a valid explanation for why it's not a demonstration for the existence of atoms. you can't just say it without an explanation.
the fact that air can get in doesn't prove my explanation wrong. as the water leaves, air takes its place.

DrClaude
Mentor
give me a valid explanation for why it's not a demonstration for the existence of atoms. you can't just say it without an explanation.
You simply have a fluid that splits up. You don't need atoms for that.

I quote you again:
if there were no spaces between the atoms, the water would all flow out uniformly and consistently
That's a non-sequitur. It's up to you to prove that the conclusion follows from the premise.

why does the water come out in clumps?
Because otherwise the water blocks the air from coming in. If you take the bottle upside down and turn fast to create a vortex, you will see all the water flowing out continuously.

that sarcastic comment didn't answer anything. I know that air fills the bottle as the water is pouring out. why does the water come out in clumps?
It could be explained by complex fluid dynamics (both the liquid and the air are fluids)
In rough terms, an oscillation is being set up in which some fluid flows out, then some air flows back in.
The exact frequency of that oscillation will involve many factors including atmospheric pressure, the density of the liquid, the diameter of the drain, hole, the geometry of the bottle and probably a lot more, but it's computable in principle, given a bit of chaos theory to mix up up things a bit.

It could be explained by complex fluid dynamics (both the liquid and the air are fluids)
In rough terms, an oscillation is being set up in which some fluid flows out, then some air flows back in.
The exact frequency of that oscillation will involve many factors including atmospheric pressure, the density of the liquid, the diameter of the drain, hole, the geometry of the bottle and probably a lot more, but it's computable in principle, given a bit of chaos theory to mix up up things a bit.
just agree with drclaude

Is your point that because the substance is "divisable" it must be made of constituants?

There are just a couple of molecular bonds, one of those bond types describes how things like water "sticks" together with a certain amount of force. Clearly that force is comparatively weak (to many chemical bonds for example) such that gravity easily overcomes it. This bonding amongst molecoles (not atoms!) would describe the surface tension of water...for example. I think it's the same mechanics that gives a liquid it's viscosity at whatever temperature (as in even small changes in temperature can over come this bond i.e. evaportion)

Is your point that because the substance is "divisable" it must be made of constituants?

There are just a couple of molecular bonds, one of those bond types describes how things like water "sticks" together with a certain amount of force. Clearly that force is comparatively weak (to many chemical bonds for example) such that gravity easily overcomes it. This bonding amongst molecoles (not atoms!) would describe the surface tension of water...for example. I think it's the same mechanics that gives a liquid it's viscosity at whatever temperature (as in even small changes in temperature can over come this bond i.e. evaportion)

ZapperZ
Staff Emeritus
Your acceptance of that answer doesn't make sense at all, because it definitely does not support your original claim.

If you pour this at an angle, allowing for air to continue to come in without any interruption, you DO NOT get these globs of water coming out. So already this negates your idea, since I can make it so that it has a laminar flow out of the bottle.

Zz.

DrClaude
Mentor
The discussions around atomistic theory were never about whether matter could be broken into smaller parts, but whether there was a smallest unit of something. Do you think that Aristotle never noticed that when he hate is soup, some of the liquid would break off into his spoon, and the rest stayed in the bowl?

What you have observed can all be described by classical fluid dynamics. But in CFD, there are no atoms: the fluid can be broken down into infinitely small volumes and still retains its characteristics (density, viscosity, etc.) We know that this is not realistic, but that can't be seen from a liquid pouring out of a bottle.

Your acceptance of that answer doesn't make sense at all, because it definitely does not support your original claim.

If you pour this at an angle, allowing for air to continue to come in without any interruption, you DO NOT get these globs of water coming out. So already this negates your idea, since I can make it so that it has a laminar flow out of the bottle.

Zz.
your right. I was just going to take back the acceptance, because I too have come to the conclusion that splitting anything in half is a proof of atoms