# How does density affects gas pressure?

1. Jul 12, 2013

### threy

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.

2. Jul 12, 2013

### Aero_UoP

Equation of state for an ideal gas: p=ρRT

3. Jul 12, 2013

### jbriggs444

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.

4. Jul 13, 2013

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,