Rms velocity of H at 300K is 1.9 into 10 rasied to 3 m/s. The rms velocity of O at 1200K will be?

V_RMS=ROOT 3RT/M

so,
 rms for o=root 3*8.314*1200/16*10^-3
              =root 9*8.314*10⁵/4
             =root 74.826*10⁵/4
            =root 1.87*10⁶
            = 1.36*10³ m/s


i hope it will help:)