If the r.m.s. velocity of a gas at a given temperature (Kelvin scale) is 300 m/s, whathat will be the r.m.s. velocity of a gas having twice the molecular weight and half the temperature on Kelvin scale =
vmax = √3RTM⇒Vmax∞√TM
v2v1 = √M1M2×T2T1√12×12 ⇒v2=v12=3002=150m/sec