Question

Select the answer which shows the correct order, slowest to fastest, of the relative rate of diffusion of the gases.

Answer 1

Answer: Option (a) is the correct answer.

Explanation:

According to Graham's law, rate of diffusion or effusion is inversely proportional to the square root of molecular weight.

Mathematically,      Rate of diffusion or effusion = $\sqrt {\frac{1}{M}}$

where            M = mass or molecular weight of gas

Therefore, in the given options, mass of the gases is as follows.

   Nitrogen = 14.00 g/mol

   Neon = 20.17 g/mol

   Argon = 39.94 g/mol

   Krypton = 83.79 g/mol

Hence, more is the mass of gas less will be its rate of diffusion. Thus, we can conclude that correct order from slowest to fastest will be as follows.

                                  Kr < Ar < Ne < N

Answer 2

The heavier the gas is, the slower the gas will diffuse.  the correct order is Kr, Ar, Ne, N based off of the atomic weight.  However I don't think N is a gas.  Nitrogen is diatomic so it should be N₂.

I hope this helps.