X ml of H₂ gas effuses through a hole in a container in 5 seconds. The time taken for the effusion of the same volume of the gas specified below under identical condition is

Rate of diffusion = Volume diffused time taken 1 1 1 2 2 2 2 1 1 2 v r t t M v r t M t (a) 10 seconds: He 10 4 5 2 (b) 2 20 seconds : O 20 32 5 2 (c) 25 seconds : CO 25 28 5 2 (d) 2 55 seconds : CO 55 44 5 2 Thus, the correct answer is (b)