Explanation

The excluded volume is represented by "b"

Concept:

The constant 'b' is the van der Waals constant for correction in volume.

It is also known as the excluded volume or co-volume.

The numerical value of 'b' is found to be four times the actual volume occupied by the gas molecules.

Formula:

Excluded volume or co-volume equals (V−nb) for n moles.

Reason: Co-volume depends on the effective size of gas molecules.