At 25 degrees C, a sample of NH3( molar mass 17 g) effuses at the rate of .050 mole per minute. Under the same conditions, which of the following gases effuses at approxiomatesly half that rate?

Question

A- O2
B- He2
C-CO2
D-CI2
E-CH4

Answer 1

(rate 1/rate 2) = (mm 2/mm 2) where mm is molar mass.

(0.05/0.025) = (mm 2/17)
solve for mm and compare with the answers. The answer is approximate; pick the closest gas.