How does density affects gas pressure?

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    Density Gas Pressure
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Discussion Overview

The discussion centers on the relationship between gas density and gas pressure, exploring theoretical aspects and implications of the ideal gas law. Participants examine how density influences the behavior of gas molecules and their interactions with container walls.

Discussion Character

  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant suggests that higher density results in more gas molecules, leading to increased pressure due to a higher rate of collisions with container walls.
  • Another participant presents the ideal gas law equation, p=ρRT, indicating a relationship between pressure, density, and temperature.
  • A later reply agrees with the initial claim, stating that more molecules hitting a given area results in higher force per unit area, assuming constant temperature and small molecular size relative to the space between them.
  • Another participant defines density and discusses how gases of different densities exert different pressures based on their mass and momentum changes upon collision with walls.

Areas of Agreement / Disagreement

Participants generally agree that higher density leads to increased pressure due to more frequent collisions of gas molecules with container walls. However, there are nuances in the explanations provided, and some aspects remain open to further discussion.

Contextual Notes

Some assumptions regarding the ideal gas behavior, temperature constancy, and the size of gas molecules relative to their spacing are present but not fully explored or resolved.

threy
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When density is higher, the gas contains more gas molecules. Gas molecules collide with the walls of container to produce an average force known as gas pressure. Therefore the increase in gas molecules will result in the increase of pressure because the rate of collision is higher. Is that right?? Please help.
 
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Equation of state for an ideal gas: p=ρRT
 
threy said:
When density is higher, the gas contains more gas molecules. Gas molecules collide with the walls of container to produce an average force known as gas pressure. Therefore the increase in gas molecules will result in the increase of pressure because the rate of collision is higher. Is that right?? Please help.

Yes. That is right. More molecules hitting a given area on the wall per unit time and delivering the same impulse on average per hit means a higher force per unit area.

If temperature is kept constant and if the size of the gas molecules is small compared to the space between them, pressure is approximately proportional to the number of gas molecules per unit volume.
 
Density is mass per unit volume,

Let me take two gases of unit volume, having different densities,

The gas which has less density has less mass,

The gas which has more density has more mass,

when these gas molecules hit the wall, because of change in momentum pressure will be applier on the wall,

change in momentum = m x ΔV

which ever gas has more mass applies more pressure on the wall,

hope it clears your doubt...
 

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