Why is Dalton's Law a limiting law?

Answer 1

A limiting law is such a law that is strictly true in a certain limit.

Now, Dalton's law states that: The pressure exerted by a mixture of gases is the sum of the pressures that each one would exert if it occupied the container alone.

The law that the sum of the partial pressures equals the total pressure is true for real and perfect gases.Whereas, the identification of partial pressure with pressure that a gas would exert on its own is only valid for a perfect gas.

So now we see that Dalton's law is only valid for perfect gases, hence it is a limiting law.

Hope that helps.

Answer 2

Dalton's Law is a limiting law because it assumes ideal gas behavior, which may not hold true under certain conditions. It also assumes that the gases in the mixture do not interact with each other, leading to inaccuracies in predicting the behavior of real gases.