Two gases A and B having the same volume diffuse through a porous partition in 20 and 10 seconds respectively. The molecular mass of A is 49 u. Molecular mass of B wil be :
(1) 12.25 u
(2) 6.50 u
(3) 25.00 u
(4) 50.00 u
(1) 12.25 u
(2) 6.50 u
(3) 25.00 u
(4) 50.00 u