# Physical Chemistry: Estimating ΔG of an Ideal Gas

• Nick_273

## Homework Statement

Estimate ΔG for the process where one mol of ideal gas is subjected to an increase in
pressure from 1.00 atm to 11.0 atm at 25.0°C.

ΔG=ΔH-TΔS
ΔH=C(p,m)(Tf-Ti

## The Attempt at a Solution

Seems straight forward, but it seems i am not given enough information to complete the problem. I need C(p,m)? It does say estimate. Does that mean that i only need to imply that the Gibbs free energy will be possitive, negative, or 0?

If you can help me clarify the problem that would be greatly appreciated!

Thanks.

Does the problem say whether the ideal gas is monatomic or diatomic?

No, it does not. Does this equation apply?

ΔG = nRTln(Pf/Pi)

I found it in my notes but can't find it anywhere in the text.

Oh, for this case, you can actually still calculate ΔH even though you do not know the heat capacity of the gas.

Hi Nick_273!

No, it does not. Does this equation apply?

ΔG = nRTln(Pf/Pi)

I found it in my notes but can't find it anywhere in the text.

Yep, it applies (for an isothermal process on an ideal gas).