Under what condition will diffusion take place most rapidly?

Question

a
movement from an area of high concentration to an area of low concentration
b
movement through a permanent barrier
c
movement against a concentration gradient
d
movement from an area of low concentration to high concentration

Answer 1

a. movement from an area of high concentration to an area of low concentration

Diffusion occurs most rapidly when it moves from an area of high concentration to an area of low concentration, as this is the natural process by which substances tend to equalize concentration differences.