The molecules of a given mass of a gas have a rms velocity of 200 m/s at 270C, pressure 1.0 x 105 N/m2 at 1270C and pressure is 0.5 x 105 N/m2, the rms velocity in m/sec will be

Vrms=3RTM ⇒Vrms α T given temperature T1=27+273=300K;V300o=200m/s T2=127+273=400K;substitute in the  equation V1V2=T1T2 ⇒V300oV400o=300400=34 ⇒200V400=34⇒V400=(200)(2)3=4003m/s=Vrms