What do the different colour heart emojis mean? Does a red , yellow , green , blue and violet emoji all mean the same thing according to you? Solitude4
1 The relative atomic mass, or atomic weight, of an element is the weighted average of the masses of the isotopes in the naturally occurring element relative to the mass of an atom of the carbon-12 isotope which is taken to be exactly 12.
Nipun's answer is absolutely correct when you need to find relative rates of diffusion. This means, given that we know the rate of diffusion for one chemical compound, we can find it for another knowing their masses. If you need to determine this rate theoretically for a single mass without a reference, you can use Fick's laws of diffusion (Fick's laws of diffusion) but also read about Diffusion here.