Speed (rms) = sqrt 3KT/m, where:
K = Boltzmann's costant = 1.38*10^-23 joule/K;
T = temperature in Kelvin degrees = 273 - 63 = 210 K;
m = 44 * 1.672*10^-27 Kg;
1.672*10^-27 Kg (good approximation) is the weight of a single a.m.u. (atomic mass unit);
44 is molecular weight of CO2.
Molecular Speed (CO2) = sqrt 3*1.38*10^-23*210/44*1.672*10^-27 = 344 m/sec.
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