What is the average speed (actually the root-mean-square speed) of a argon atom at 27°C?

T = temperature of argon atom = 27 °C

in kelvin, temperature is given as

T = temperature of argon atom = 27 + 273 = 300 K

M = mass of atom of argon = 39.9 x 10⁻³ kg/mol

R = gas constant = 8.314

v = root mean square speed

root mean square speed is given as

v = sqrt (3RT/M)

inserting the values

v = sqrt (3 (8.314) (300) / (39.9 x 10⁻³))

v = sqrt (7482.6 / (39.9 x 10⁻³))

v = sqrt (187533.835)

v = 433.1 m/s