Question

(V-nb)=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 carbon dioxide the numerical value of a is 3.592atm and the numerical value of b is 0.0429atm
Use the van der Waals equation to calculate the pressure of a sample of carbon dioxide at 45.0 °C with a molar volume of 0.257 L/mol. Round your answer to 3 significant digits.
Use the Ideal Gas Law to calculate the pressure of the same sample under the same conditions. Round this answer to 3 significant digits .

Answer 1

The units of a in the van der Waals equation are (L².atm/mol²), and the units of b are (L/mol). The pressure of the carbon dioxide sample is calculated using both the van der Waals equation and the Ideal Gas Law.

Step-by-step explanation:

The units of constant a in the van der Waals equation are (L².atm/mol²). This is derived by multiplying the units of pressure (atm) by the square of the units of moles (mol).

The units of constant b in the van der Waals equation are (L/mol). This represents the volume occupied by one mole of gas particles.

To calculate the pressure of a sample of carbon dioxide at 45.0 °C with a molar volume of 0.257 L/mol using the van der Waals equation, you can substitute the given values into the equation: (3.592 - (0.0429 * 0.257/0.0441)) * (0.257 / (0.257 - (0.0429/0.0441))) * 0.0441 * (273.15 + 45). The result is the pressure of the carbon dioxide sample.

To calculate the pressure of the same carbon dioxide sample using the Ideal Gas Law, you can substitute the given values into the equation: (3.592 * (0.257 / (0.257 - (0.0429/0.0441)))) * (273.15 + 45) / 0.0441. The result is the pressure of the carbon dioxide sample.