Compute the root-mean-square speed of Ar molecules in a sample of argon gas at a temperature of 72C

Answer 1

This is the same as before only the temperature has changed. You do it the same way..

μ_rms = sqrt 3RT/M

R = 8.3145 J/mol-K

T = temperature in K = 72C + 273 = 345K

M = molar mass in kg/mol. For Ar this is 39.95/mol x 1kg/1000g = 0.03995 kg/mol

μ_rms = sqrt [(3 x 8.3145 x 345) / 0.0.03995)] = sqrt 215,407

μ_rms = 464 m/sec