Derive the density of an ideal gas as a function of temperature?

AI Thread Summary
The discussion focuses on deriving the density of an ideal gas as a function of temperature while maintaining constant pressure. The key equation presented is density = PM/(RT), where M is the molecular weight and R is the gas constant. Participants express confusion about the relationship between density, temperature, and the conditions of expansion or compression. It is clarified that the density's relationship to temperature remains unchanged regardless of whether the gas is expanding or compressing at constant pressure. The conversation emphasizes the importance of understanding how temperature affects density in the context of the ideal gas law.
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derive the density of an ideal gas as a function of temperature??

Homework Statement


Derive the density of an ideal gas when it is allowed to expand as a function of temperature when pressure is kept constant/


Homework Equations





The Attempt at a Solution


density= PM/(RT) , where M is the molecular weight
or ∂ρ/∂T =M/(RT)
or ρ(V,P),then keep P constant, ∂ρ/∂V =∂<PM/(RT)>

actually i am not sure what the question asking about . Thank you
 
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Outrageous said:

Homework Statement


Derive the density of an ideal gas when it is allowed to expand as a function of temperature when pressure is kept constant/

Homework Equations


The Attempt at a Solution


density= PM/(RT) , where M is the molecular weight
or ∂ρ/∂T =M/(RT)
or ρ(V,P),then keep P constant, ∂ρ/∂V =∂<PM/(RT)>

actually i am not sure what the question asking about . Thank you
Relate the mass of the gas to the volume using the ideal gas equation. Use n = m/M where m is the mass of the gas and M is the molecular weight or mass/mole of the gas.

What is n/V? How is n/V related to density of the gas?

AM
 


m/V is density of gas system
n /V is density of gas molecule?
I don't know how to relate.
 


Outrageous said:
m/V is density of gas system
... and since m = nM... the density of the gas is ... (in terms of M, P, R and T).

AM
 


Outrageous said:

Homework Statement


Derive the density of an ideal gas when it is allowed to expand as a function of temperature when pressure is kept constant/

The Attempt at a Solution


density= PM/(RT) , where M is the molecular weight
or ∂ρ/∂T =M/(RT)
or ρ(V,P),then keep P constant, ∂ρ/∂V =∂<PM/(RT)>

actually i am not sure what the question asking about . Thank you

So the question want density in terms of P M R T? Then why does the question say when it expand?
 


Outrageous said:
So the question want density in terms of P M R T? Then why does the question say when it expand?
You should ask the person who drafted the question...it was probably asked this way to just give it some context. What the question is asking is the relationship between T and m/V with constant P. Whether it is expanding or being compressed at constant P makes no difference to the relationship.

AM
 


Andrew Mason said:
Whether it is expanding or being compressed at constant P makes no difference to the relationship.

AM

Thank you.
 
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