Chapter 19, Problem 19.64E

Interpretation Introduction

Interpretation:

The reason as to why the diffusion stops when a solute gas is evenly spread in a system of solvent gas is to be stated.

Concept introduction:

Fick’s first law of diffusion gives the relation between diffusion and the concentration gradient in $x$ direction. The expression for Fick’s first law of diffusion is,

$\frac{d{N}_1}{dt}=-D\cdot A\cdot \frac{d{c}_1}{dx}$

Where,

• $\frac{d{N}_1}{dt}$ gives the diffusion of gas particles.

• $D$ is the proportionality constant.

• $\frac{d{c}_1}{dx}$ is the concentration gradient in $x$ direction.

The value of constant $D$ does not depend on the identity of the gas.