Compute the root-mean-square speed of Ne molecules in a sample of neon gas at a temperature of 199°C.

Answer 1

u_rms = root mean square velocity = √(3RT/M)

R = gas constant =  8.3145 kg·m²/s²/K·mol

T = temperature in Kelvin = 199º + 273 = 472K

M = molar mass of the gas in kg = 20.18 g/mol x 1 kg/1000 g = 0.02018 kg/mol

u_rms = √(3)(8.3145)(472)/0.02018

u_rms = 764 m/s