What is Maxwell law of diffusion?

The basic assumption of the theory is that a deviation from equilibrium between the molecular friction and thermodynamic interactions leads to the diffusion flux. The molecular friction between two components is proportional to their difference in speed and their mole fractions.

What determines diffusion coefficient?

The diffusion coefficient is the proportionality between flux and concentration gradient. The electrode area can be determined electrochemically with equations equivalent to an equation and by using a redox couple having a known diffusion coefficient.

Which is the model for diffusion in multicomponent systems?

The Maxwell–Stefan diffusion (or Stefan–Maxwell diffusion) is a model for describing diffusion in multicomponent systems. The equations that describe these transport processes have been developed independently and in parallel by James Clerk Maxwell for dilute gases and Josef Stefan for fluids.

How is the diffusion coefficient of a binary system determined?

Only the diffusion coefficients for the binary and ternary case can be determined with reasonable effort. In a multicomponent system, a set of approximate formulas exist to predict the Maxwell–Stefan-diffusion coefficient.

How is the diffusive mass flux of a species expressed?

The diffusive mass flux of each species is, in turn, expressed based on the gradients of the mole or mass fractions, using multi-component diffusion coefficients Dik. These are symmetric, so that an n -component system requires n ( n -1)/2 independent coefficients to parameterize the rate of diffusion of its components.

What is the Assumption in the diffusion equation?

The equation assumes steady state, i.e., the neglect of time derivatives in the velocity. The basic assumption of the theory is that a deviation from equilibrium between the molecular friction and thermodynamic interactions leads to the diffusion flux. The molecular friction between two components is proportional…