the average velocity of gas particles is found using the root mean square velocity formula

μ rms = (3RT/M) ½

where μ rms = root mean square velocity in m/sec R = ideal gas constant = 8.3145 (kg·m 2 /sec 2 )/K·mol T = absolute temperature in Kelvin = 105+273 = 378 M = mass of a mole of the gas in kg = 28 g /mol = 0.028 kg / mol