Question

In positive deviation which vanderwaal constant is neglegible

Answer 1

The behavior of real gases usually agrees with the predictions of the ideal gas equation to within 5% at normal temperatures and pressures. At low temperatures or high pressures, real gases deviate significantly from ideal gas behavior. ... It also assumes that the force of attraction between gas molecules is zero.


So no, carbon dioxide is not an ideal gas because it has attractive and repulsive forces between particles, gas particles have a volume, and the collisions are not elastic. Generally speaking, a real gas approaches ideal behavior in high temperatures and low pressures.