ANS:A - exponential

The partial pressure distribution of an ideal gas diffusing through another stagnant ideal gas at steady state actually follows an exponential law. In the context of diffusion, an exponential distribution is observed when the concentration or partial pressure of a substance decreases exponentially as distance from the source increases. This phenomenon is governed by Fick's Law of Diffusion, which states that the rate of diffusion of a substance is proportional to the concentration gradient. In mathematical terms, the exponential decrease in partial pressure (or concentration) with distance 𝑥x from the source can be expressed as: 𝑃=𝑃0×𝑒−𝑥𝐿P=P0​×e−Lx​ Where:

• 𝑃P is the partial pressure of the substance at a distance 𝑥x from the source,
• 𝑃0P0​ is the initial partial pressure of the substance at the source,
• 𝑒e is the base of the natural logarithm (approximately equal to 2.71828),
• 𝐿L is the characteristic length scale of the diffusion process, known as the diffusion length.

This equation demonstrates that as 𝑥x increases, the partial pressure decreases exponentially due to the exponential term 𝑒−𝑥𝐿e−Lx​. Therefore, the partial pressure distribution of an ideal gas diffusing through another stagnant ideal gas at steady state follows an exponential law. Thank you for bringing this to my attention!