text: Ok well the first thing to remember is that temperature is really just a measure of the kinetic energy in a material. That is, how fast the particles are moving.\n\nIn a cold material the atoms are moving about very slowly, but as the temperature increases the speed and energy of the particles increases. \n\nNow diffusion can be said to be the rate at which particles mix with each other or the rate at which they intermingle through random thermal motion. Obviously if they are moving faster, they will mix faster. And if they are moving slow they will mix slow.\n\nAs an example think of a jar of different colour sand layers, if you shake the jar slowly the sands will mix slowly, but if you shake it very fast the sands will mix very quickly. Same thing with molecules.