Final answer:
The rate of diffusion is inversely proportional to molecular size, with larger molecules diffusing more slowly than smaller ones. Temperature affects molecular speed, thus influencing diffusion, while solution density is inversely proportional to the rate of diffusion. Greater distances also result in slower diffusion rates.
Step-by-step explanation:
Relationship Between Molecular Size and Rate of Diffusion
The rate of diffusion of a molecule is inversely related to its size. Larger molecules tend to move slower than lighter ones because they have more mass, leading to a reduced diffusion rate. This is because the average molecular speed at a given temperature is inversely proportional to the molecular mass. Additionally, as molecules become heavier, the diffusion constant (D) decreases, further slowing down diffusion. Temperature plays a significant role as well, where increased temperature leads to an increase in molecular speed and hence a higher diffusion rate. Conversely, as temperature decreases, molecular movement slows down, leading to a slower diffusion rate. With regard to solution density, the rate of diffusion is inversely proportional; denser solutions hinder molecular movement. Finally, distance directly affects diffusion: the greater the distance that must be traveled, the slower the overall rate of diffusion will be.