n=number of moles=7.7 moles.
P=pressure at atm=0.09 atm
T=temperature at ºK=329 ºK
R=universal gas costant=0.082 (L*atm ) / (ºK*mol)
The ideal gas law:
PV=nRT
therefore:
0.09 atm*V=7.7 moles * 0.082 (L*atn)/(ºK* mol) * 329ºK
V=(7.7 moles * 0.082 (L*atn)/(ºK* mol) * 329ºK) / (0.09 atm)=2,308.12 L
Answer: the volume is 2,308.12 litres