What is the Difference Between Graham’s Law of Effusion and Diffusion?

Graham's Law of Effusion and Diffusion are related to the behavior of gases in different contexts. Here are the main differences between the two:

1. Process:

• Effusion: This occurs when a gas passes through an opening that is smaller than the mean free path of the particles, meaning that only one particle can pass through at a time. Effusion is the process by which a gas escapes through a pinhole into a vacuum.
• Diffusion: This is the gradual mixing of gases due to the motion of their component particles, resulting in a gas mixture with a uniform composition. Diffusion also occurs in liquids and solid solutions to a lesser extent.

1. Rate:

• Graham's Law of Effusion states that the rate of effusion of a gas is inversely proportional to the square root of its molecular mass. Lighter gases effuse more rapidly than heavier ones.
• Graham's Law of Diffusion states that the rate of diffusion of a gas is inversely proportional to the square root of its molecular mass.

1. Application:

• Effusion is used to describe the behavior of gases when they escape through small openings, such as tiny holes in a balloon.
• Diffusion is used to describe the behavior of gases when they spread out and mix with each other in a container.

In summary, effusion is the process of gases escaping through small openings, while diffusion is the process of gases mixing and spreading out in a container. Graham's Law of Effusion and Diffusion states that the rate of these processes is inversely proportional to the square root of the molecular mass of the gases involved.

Comparative Table: Graham’s Law of Effusion vs Diffusion

Graham's Law of Effusion and Diffusion are related phenomena, but they differ in their definitions and applications. Here is a table highlighting the differences between the two:

Both effusion and diffusion are influenced by the molecular weight of the gas. However, effusion is specifically related to the movement of gas molecules through a small hole, while diffusion is concerned with the gradual mixing of gases. Graham's Law states that the ratio of the rates of diffusion or effusion of two gases is directly proportional to the inverse ratio of their molar masses.