What is the Difference Between Ideal Gas Law and Van der Waals Equation?

The ideal gas law and the Van der Waals equation are both equations used to describe the behavior of gases. However, they differ in their applicability and the assumptions they make about gas behavior.

Ideal Gas Law:

• The ideal gas law is a fundamental law that describes the relationship between pressure (P), volume (V), amount (n), and temperature (T) of a gas. The formula is $$PV = nRT$$, where R is the gas constant).
• It assumes that gas particles have no volume and do not interact with each other, which is not entirely accurate for real gases.
• The ideal gas law is only applicable to ideal gases, which are hypothetical and do not exist in reality.

Van der Waals Equation:

• The Van der Waals equation is a modified version of the ideal gas law that accounts for the deviations from ideal gas behavior, such as the volume of gas particles and intermolecular interactions.
• The equation contains a pair of constants (a and b) that change from gas to gas. These constants allow for the correction of the size of the gas molecule and the interactions between them.
• The Van der Waals equation can be used for both ideal gases and real gases.
• It was developed by Johannes Diderik van der Waals, who was awarded the Nobel Prize in 1910 for his work on the equation of state for gases and liquids.

In summary, the main differences between the ideal gas law and the Van der Waals equation are that the ideal gas law is applicable only to ideal gases and assumes no volume and no interactions between gas particles, while the Van der Waals equation accounts for the deviations from ideal gas behavior and can be used for both ideal and real gases.

Comparative Table: Ideal Gas Law vs Van der Waals Equation

The Ideal Gas Law and Van der Waals Equation are both equations that describe the behavior of gases. However, they differ in their assumptions and predictions, mainly due to the fact that real gases deviate from ideal gas behavior under certain conditions. Here is a comparison table highlighting the differences between the two equations:

The Van der Waals equation is a modification of the Ideal Gas Law that takes into account the molecular size of gas particles and the intermolecular forces between them. This modification allows the Van der Waals equation to provide a more accurate description of the behavior of real gases under non-ideal conditions, while the Ideal Gas Law is more suitable for predicting the behavior of ideal gases.