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Moderate

Real Gas vs. Ideal Gas

APCHEM-HIY4GA

In theory, 1.00 mol of water vapor in a 10.0 L container at 400 K should have a pressure of 3.28 atm, according to the ideal gas law. However, the observed pressure is actually 3.24 atm.

Which of the following is the best justification for why the observed pressure is slightly less than the predicted value?

A

Water molecules tend to travel at faster speeds than other gas molecules.

B

Water molecules experience intermolecular attractive forces with each other.

C

Water molecules tend to bounce off each other with a large repulsive force.

D

Water molecules experience adhesion with the walls of the container.