Question

The diffusion mechanism that involves atoms moving through vacancies in a solid is called:

• A. Interstitial diffusion
• B. Vacancy diffusion
• C. Grain boundary diffusion
• D. Surface diffusion

Hint:

Vacancy diffusion = atoms hop into nearby empty spots. Interstitial diffusion involves smaller atoms squeezing through spaces between larger ones.

Answer 1

The Correct Option is B

Vacancy diffusion is a mechanism of atomic movement in solids where atoms migrate by jumping into adjacent vacant lattice sites (vacancies).
This mechanism is prominent in substitutional solid solutions where atoms move from one site to another by occupying nearby vacancies.
It is one of the key mechanisms of diffusion, especially in crystalline materials, and its rate depends on the concentration of vacancies and the activation energy required for atomic movement.
Thus, the diffusion mechanism involving atoms moving through vacancies is called vacancy diffusion.