Can Gas Pressure Exceed Out Pressure?

In summary, the conversation discusses the possibility of gas pressure being higher than outside pressure and its effects on liquid turning into vapor. It is clarified that vapor pressure cannot exceed ambient pressure and an example is given involving super-heated water. The conversation concludes with the understanding that decreasing the temperature of the liquid is the only way to prevent it from turning into gas.
  • #1
jukzzhd
8
0
i wonder if "gas pressure > out pressure" this can be possible. if so how?
 
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  • #2
Ahem. What?
 
  • #3
voko said:
Ahem. What?
Copy that...
 
  • #4
sorry for bad translation. that was all i can do
 
  • #5
I do not understand the question in #1. Rephrase it.
 
  • #6
jukzzhd said:
sorry for bad translation. that was all i can do
It is not a translation problem, it is a description problem. You only gave us part of one sentence! Please write a much longer description of the problem and translate that.
 
  • #7
as we know when the gas pressure of a liquad is equal with the outside pressure, liquid starts to boil. I am asking that if the gas pressure of a liquid can be "bigger" than the outside pressure.
and yeah its both description and translation problem
 
  • #8
jukzzhd said:
as we know when the gas pressure of a liquad is equal with the outside pressure, liquid starts to boil
No, that is not true. At every free air-water interface (every lake, river, sea) the pressures are exactly equal. Is there any boiling?
 
  • #9
That would be a translation/comprehension issue: tjukzzhd is referring to vapor pressure.

The answer is no, the saturation pressure in the liquid cannot be higher than the vapor pressure outside of it. If it tries to be, the water just instantly flashes to steam (this happens when hot, pressurized water flows through a valve or nozzle, lowering its pressure).
 
  • #10
russ_watters said:
If it tries to be, the water just instantly flashes to steam

I am not sure I follow this. You said the question was about vapor. If vapor pressure exceeds ambient pressure, then it just expands, possibly part of it condensing or even solidifying in the process.

But then you gave an example involving a liquid, not vapor. What are we really discussing here?
 
  • #11
voko said:
I am not sure I follow this. You said the question was about vapor. If vapor pressure exceeds ambient pressure, then it just expands, possibly part of it condensing or even solidifying in the process.

But then you gave an example involving a liquid, not vapor. What are we really discussing here?
Not vapor, vapor pressure. We're talking about what is happening in the liquid and if/why it turns to gas. Saturation pressure and vapor pressure are equal here.
 
  • #12
What about super-heated water? I heard if you microwave deionized water in a clean cup you can get this.
 
  • #13
Khashishi said:
What about super-heated water? I heard if you microwave deionized water in a clean cup you can get this.
Heat and cool several times in a smooth container which does not promote bubbling to increase probability.

But the only way is to decrease temperature of the liquid, at a high enough temperature every liquid turns to gas... the atmospheric pressure keeping bubbles in is comparatively minor in respect to that.
 

FAQ: Can Gas Pressure Exceed Out Pressure?

Can gas pressure exceed atmospheric pressure?

Yes, gas pressure can exceed atmospheric pressure in certain situations. Atmospheric pressure is the pressure exerted by the weight of the air above us, and it can vary based on altitude and weather conditions. Gas pressure, on the other hand, is the force exerted by gas molecules colliding with the walls of a container. If the temperature and number of gas molecules inside a container increase, the gas pressure will also increase and can exceed atmospheric pressure.

What factors can cause gas pressure to exceed out pressure?

Gas pressure can exceed out pressure due to a variety of factors. These include increasing the temperature of the gas, increasing the number of gas molecules present, and decreasing the volume of the container. Additionally, chemical reactions, such as combustion, can also cause an increase in gas pressure.

Is it dangerous if gas pressure exceeds out pressure?

It can be dangerous if gas pressure exceeds out pressure, especially if it happens suddenly and without warning. This can lead to explosions or ruptures of containers, which can cause harm to individuals and property. It is important to carefully monitor and control gas pressure to prevent any potential hazards.

How can gas pressure be controlled to prevent it from exceeding out pressure?

Gas pressure can be controlled through a variety of methods. One way is to regulate the temperature of the gas, as increasing the temperature can lead to an increase in pressure. Another way is to limit the amount of gas present in a container, as the number of gas molecules affects the pressure. Using safety devices such as pressure relief valves can also help to prevent gas pressure from exceeding out pressure.

What happens if gas pressure exceeds out pressure in a pressurized system?

If gas pressure exceeds out pressure in a pressurized system, it can lead to catastrophic failure of the system. This can result in explosions, ruptures, and other hazardous situations. It is important to regularly inspect and maintain pressurized systems to prevent any potential failures due to excessive gas pressure.

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