Chapter 5, Problem 128AE

Interpretation Introduction

Interpretation:The simplification of Van der Waals equation to ideal gas equation under low pressures and high temperatures need to be shown.

Concept Introduction:The expression relating the pressure, P, volume, V with number of moles, n and temperature, T of an ideal gas is:

  $\text{PV = nRT}$ (obtained by combining three gaseous laws: Charles’s law, Boyle’s law and Avogadro’s law)

Where R is Universal gas constant.

The ideal gas is accepted under low pressures and high temperatures.

The modified ideal gas equation is termed as Van der Waals equation that governs the behaviour of real gases. The Van der Waals equation is written as:

  $\left[\text{P + a}{\left(\frac{\text{n}}{\text{V}}\right)}^{\text{2}}\right]\left(\text{V - nb}\right)\text{ = nRT}$

Where a represents measure of intermolecular attraction and b represents measure of size of the molecule.