Question

the ratio of the rate of diffusion of a given element to that helium is 1.414:1 the molecular weight of the elements​

Answer 1

R1/r2=√m2/√m1

1.4=√4/√m1

squaring both sides:

1.96=4/m1

m1=4/1.96=2.04

Answer 2

The molecular weight of the element is 2

• Given, Ratio of Rate of diffusion of given element to Helium is 1.414 : 1
• Molecular weight of Helium = 4 g/mole
• Also, according to Graham's law of diffusion
• The rate of diffusion and Molecular weights are related as                                       R1/R2 = $\sqrt{M2/M1\\}$
• From the data and the law,                                                                                1.414/1 = $\sqrt{4/M1}$    
• Squaring on both sides  we get  
• 2 = 4 / M1  ;  M1 = 2