C2F4 effuses through a barrier at a rate of 4.6x10-6 mol/hour, while an unknown gas effuses at a rate of 5.8x10-6 mol/hour. What is the molar mass of the unknown compound?

The molar mass of the unknown compound is calculated as follows

let the unknown gas be represented by letter Y

Rate of C2F4 / rate of Y = sqrt of molar mass of gas Y / molar mass of C2F4

= (4.6 x10^-6 / 5.8 x10^-6) = sqrt of Y / 100

remove the square root sign by squaring in both side

(4.6 x 10^-6 / 5.8 x10^-6) ^2 = Y/100

= 0.629 = Y/100

multiply both side by 100

Y = 62.9 is the molar mass of unknown gas