Can Gas be Weighed in a Vacuum?

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    Gas Vacuum Weighing
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SUMMARY

Weighing gas in a vacuum is feasible and can be accomplished by placing a gas-filled container on a scale within a vacuum chamber. This method effectively eliminates buoyancy effects, allowing for accurate weight measurements of gases such as helium and hydrogen. The discussion highlights the misconception held by flat-earthers regarding gas pressure and gravity, emphasizing that gas has weight and is influenced by local gravitational fields. Historical experiments, including those conducted by Apollo astronauts, validate this approach.

PREREQUISITES
  • Understanding of gas laws and properties
  • Familiarity with vacuum chambers and their applications
  • Knowledge of gravitational effects on mass
  • Basic principles of buoyancy and pressure
NEXT STEPS
  • Research the principles of gas laws, particularly Boyle's and Charles's laws
  • Learn about vacuum chamber experiments and their significance in physics
  • Explore the relationship between gravity and gas pressure
  • Investigate historical experiments conducted by Apollo astronauts regarding gas measurement
USEFUL FOR

Physics students, educators, and anyone interested in the scientific principles of gas behavior and pressure, particularly in discussions countering flat-earth theories.

fourtay
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Is it possible to weight a gas in a container surrounded by a vacum? I am arguing with flat-earthers on how gas weight is determined.

I just assumed that you can weigh a gas by placing it in a container on a scale inside a vacum. I think this was wrong. Can you do this or must you weight gas another way?
 
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First, arguing with a flat-Earther is the definition of a complete and utter waste of time.

Second, yes that would work. Why would you think it would not? I'm assuming you mean a vacuum chamber, say on the surface of the Earth, not in free fall.
 
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I don't remember ever wanting to, but I think that would be a great way to weigh gasses. It totally eliminates the problem of buoyancy, and you could weigh both helium and hydrogen like all the other gasses.
 
fourtay said:
Is it possible to weight a gas in a container surrounded by a vacum? I am arguing with flat-earthers on how gas weight is determined.
Welcome!
What the argument of the flat-earthers is?
 
Lnewqban said:
What the argument of the flat-earthers is?
Phinds has it right. Better to bang your head on a wall.

How are you going to convince a fool that 2+2=4, if he flat out denies that 1+1=2?
 
fourtay said:
Is it possible to weight a gas in a container surrounded by a vacum? I am arguing with flat-earthers on how gas weight is determined.

I just assumed that you can weigh a gas by placing it in a container on a scale inside a vacum. I think this was wrong. Can you do this or must you weight gas another way?
In order to weigh something all you need is mass and gravity, gravity is a field that extends into vacuum just as in air and a "gas container" is a substance of mass , so the answer is a simple yes you can weigh it wherever you wish. But it's weight would change depending on the local gravity of the place you weighed it at.
At moon surface for example it would be many times less than on Earth etc.
 
Their argument is that there is no observable example of gas pressure without a container. They believe there is a "cap" or a "lid" to the earth. They don't believe gas pressure can be caused by gravity. I am using the argument that all gasses have weight, therefore gas pressure is caused by gravity.
One of them called me a liar when I said you can weigh gasses in a container, inside a vacuum.

And I agree, that arguing with flat-earthers is a waste of time, I find it fun to see the different mechanisms that convince these people, and to poke holes in their arguments. Not sure how much longer I will talk to them.
 
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If you could lay your hands on some Uranium Hexafluoride then you could pour some into a tin foil boat nestled on a scale.
 
fourtay said:
Is it possible to weight a gas in a container surrounded by a vacum? I am arguing with flat-earthers on how gas weight is determined.
That's easy. Weighing a gas-filled container was one of the first experiments that the Apollo astronauts did. They were so happy with the results that they took a break to celebrate...

1663520499185.png

https://wallpaperaccess.com/full/7181200.jpg
 
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fourtay said:
Their argument is that there is no observable example of gas pressure without a container...
One of them called me a liar when I said you can weigh gasses in a container, inside a vacuum.

"A learned blockhead is a greater blockhead than an ignorant one." - Benjamin Franklin

"Ignorance is preferable to error, and he is less remote from the truth who believes nothing than he who believes what is wrong." - Thomas Jefferson

"The recipe for perpetual ignorance is: Be satisfied with your opinions and content with your knowledge." - Elbert Hubbard
 
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  • #11
berkeman said:
That's easy. Weighing a gas-filled container was one of the first experiments that the Apollo astronauts did. They were so happy with the results that they took a break to celebrate...

View attachment 314318
https://wallpaperaccess.com/full/7181200.jpg
https://www.independent.co.uk/news/...best-beer-in-world-lager-brewer-a8874016.html

After 40 years of advertising its lager as "Probably the best beer in the world", Danish brewer Carlsberg has confessed that the famous slogan may not be true.
Now we have to find out on which planet it might be the best beer. I see you go for moon...

PS. The Police should remake their famous single to "drinking on the moon"
 
  • #12
fourtay said:
Their argument is that there is no observable example of gas pressure without a container. They believe there is a "cap" or a "lid" to the earth. They don't believe gas pressure can be caused by gravity. I am using the argument that all gasses have weight, therefore gas pressure is caused by gravity.
What an odd take, with no direct relevance to flat Earth that I can see. You should tell them crackpottery works better when it is simple/concise; The more features you add, the wronger it gets.

And are they unaware that the altimeter on a plane uses the difference in air pressure to measure altitude? Have they never driven up a large hill and had their ears pop?
One of them called me a liar when I said you can weigh gasses in a container, inside a vacuum.
Ok, but why bother with a vacuum? You don't need it. If you have access to an air compressor or scuba tank you can simply weigh it on a scale directly (then again empty).
 

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