real versus ideal gases

[med17]

I have been reading conflicting things about comparing a real and ideal gas.

I understand that the pressure is lower in a real gas because the IMFs decrease the collisions of the particles with eachother and the walls of the container.

I was pretty sure volume in a real gas is greater because now you have to take into account the volume of the actual particles.. however I have read that it would be less (at moderately high pressures).. how it could ever be less doesn't make sense to me..

It also says at low temperatures the volume is less than expected? Why is that

PLEASE HELP!

---

Members don't see this ad.

 

[gentlebeast]

I think the pressure or volume of real gases depends on the intermolecular forces among gas molecules.
If attractive force, real gases have lower volume, higher pressure.
If repulsive force, real gases have higher volume, lower pressure.
When the temperature is low, gas molecules have less kinetic energy to overcome attractive intermolecular forces, and thus less volume.
When the volume is low, real gases have larger volume than expected b/c volume of gas particles.

 

[gentlebeast]

I think the pressure or volume of real gases depends on the intermolecular forces among gas molecules.
If attractive force, real gases have lower volume, higher pressure.
If repulsive force, real gases have higher volume, lower pressure.
When the temperature is low, gas molecules have less kinetic energy to overcome attractive intermolecular forces, and thus less volume.
When the volume is low, real gases have larger volume than expected b/c volume of gas particles.

Sorry that I made mistakes. I looked up in TBR.
attractive force, less pressure than ideal, b/c more restriction.
um...I'm wondering why attractive forces don't make smaller volume, and then large pressure(b/c smaller volume).....

 

[kasho11]

At moderate pressures, intermolecular forces become significant and the volume is LESS than would be predicted.

At extremely high pressures, the actual gaseous molecules are larger than the space around them, so the volume they take up is MORE than would be predicted.

 

[Dasypus]

http://www.kmacgill.com/lecture_notes/lecture_notes_gas_laws.htm

Look at the first graph, of PV/RT vs P. Where the ratio dips below unity, at moderately high pressures, that's when the attractive forces are making the big difference. Where it then goes way above unity, at very high pressures, that's when the volume of the molecules themselves are making a difference.

 

[RetailBoy]

ideal:
Plow b/w her Thighs(press low, temp high)
down the Penis, up the Vagina <<< not in all cases (lower press, higher vol)

 

[Tatiana3325]

ideal:
Plow b/w her Thighs(press low, temp high)
down the Penis, up the Vagina <<< not in all cases (lower press, higher vol)

How is this not distracting during an exam......

 

[umdnjmed]

I have been reading conflicting things about comparing a real and ideal gas.

I understand that the pressure is lower in a real gas because the IMFs decrease the collisions of the particles with eachother and the walls of the container.

I was pretty sure volume in a real gas is greater because now you have to take into account the volume of the actual particles.. however I have read that it would be less (at moderately high pressures).. how it could ever be less doesn't make sense to me..

It also says at low temperatures the volume is less than expected? Why is that

PLEASE HELP!

I may be wrong but i think you are forgetting to make the distinction between the volume of the gas as a whole and the volume of the individual gas molecules.

The deviation in volume refers to the volume of the actual molecules. In an ideal gas, each individual gas molecule is considered to have zero volume but the gas as a whole still has a volume. At lower temperatures and pressures greater than 10 atm (moderately high and high), the volume of the entire gas (not the individual molecules) decreases. As a result, the spaces between the molecules are no longer as large, the individual molecules no longer have zero volume and therefore need to be taken into consideration. Thus the volume of the individual molecules actually increases at lower temperatures and moderately high pressures.