The van der Waals equation of state was designed (by Dutch physicist Johannes van der Waals) to predict the relationship between pressure p, volume V, and temperature T for gases better than the Ideal Gas Law does:
p + a(n/V)^2 - (n*b)/V = nRT
The van der Waals equation of state. R stands for the gas constant and n for moles of gas. The parameters a and b must be determined for each gas from experimental data. Use the van der Waals equation to answer the questions in the table below.
What are the units of a?
What are the units of b?
For water, the numerical value of a is 5.464 and the numerical value of b is 0.0305.
Use the van der Waals equation to calculate the pressure of a sample of water at 505.0°C with a molar volume of 2.65 L/mol. Round your answer to 3 significant digits. (atm)
Use the Ideal Gas Law to calculate the pressure of the same sample under the same conditions. Round this answer to 3 significant digits also. (atm)