Which statement correctly compares the predictions of the ideal-gas law with those of…
CHEMISTRY · Single correct · AP · Chemistry · Properties of Substances and Mixtures · Properties of Substances and Mixtures
Problem
Which statement correctly compares the predictions of the ideal-gas law with those of the van der Waals model for a real gas at high pressure?
(a) The van der Waals model predicts a higher pressure than the ideal-gas law because it adds an extra positive pressure term to account for intermolecular attractions.
(b) When the temperature is sufficiently high, the ideal-gas law and the van der Waals equation give identical pressures regardless of how large the pressure becomes.
(c) The ideal-gas law underestimates the pressure at high pressure because it neglects the finite molecular volume, whereas the van der Waals model corrects this by subtracting a volume term.
(d) At very high pressure, the ideal-gas law becomes more accurate than the van der Waals model because the a and b corrections both approach zero.