Calculate the root mean square velocity of F2, Cl2, and Br2 at 304 K.

V (rms) = √ (3RT/M)

Where R is the molar gas constant with value 8.314 and T is the temperature in Kelvin and M is the molar mass

v (rms F₂) = √ (3 x 8.314 x 304 / 38)

v (rms F₂) = 14.1 m/s

v (rms Cl₂) = √ (3 x 8.314 x 304 / 71)

v (rms Cl₂) = 10.3 m/s

v (rms Br₂) = √ (3 x 8.314 x 304 / 160)

v (rms Br₂) = 6.88 m/s