You mean continuity equation? If so, the answer is no.  Diffusion terms of all species cancel each other in the continuity equation. They just appear in the species transport conservation equation. 

Dear Hamidreza,

Your answer is based on one model of the continuum, which is usually presented in textbooks. However, this model originally built so that the diffusion of the members was not, "evidence" on the basis of this model is only the tautologies. In this model, the accounting chaotic thermal motion violates the condition of continuity of the fluids. For example, you can see the article in the attachment.

Lev