Rate of diffusion is affected by different factors. Of the situations below, predict which one would have the fastest rate of diffusion:
a) Methylene blue that is highly concentrated in a semisolid.
b) Congo red that is highly concentrated in a semisolid (molecular weight: 697 g/mol).
c) Methylene blue that is highly concentrated in a liquid (molecular weight: 320 g/mol).
d) Congo red that is highly concentrated in a liquid.