The derivation of the ideal gas equation employs two assumptionsthat are invalid for real gas molecules. First, the equationassumes that the molecules of the gas have no volume, which is nottrue for real molecules. Since the molecules will have somephysical volume, the volume that the gas molecules occupy will beincreased by the volume that the molecules occupy at rest. Inaddition, the equation ignores any interactions among themolecules. However, such interactions were first observed in the19th century by J. D. van der Waals. He realized that, because ofthe intermolecular forces in the gas, there is a small butmeasurable attraction among the molecules, which will reduce thepressure of the gas on the walls of the container. To correct forthese two deviations from an ideal gas, the van der Waalsequation gives


where aand bare empirical constants, which are different for differentgasses.
For carbon dioxide gas (, the constants in the van der Waals equation area=0.364\;{\rm J \cdot m^{3}/mol^{2}} and b=4.27 \times 10^{-5}\;{\rm m^{3}/mol}.
Part A
If 1.00 {\rm mol} of \rm{CO_{2}} gas at 350 {\rm K} is confined to a volume of 400 {\rm cm^{3}}, find the pressure p_ideal of the gas using the ideal gas equation.
Express your answer numerically inpascals.
Part B
Find the pressure p_vdW of the gas using the van der Waals equation.
Express your answer numerically inpascals.