50 ml of hydrogen difuses out through a small hole from a vessel in 20 minutes.The time needed for 40 ml of oxygen to diffuse out is ___.
64 min
If 40 ml O2 will diffuse in t min ,so, rO2=40t
rH2=5020⇒rO2=rH2√MH2MO2=5020√232=5020×14
40t=5080∴t=40×8050=64 min