Question

If the temperature of the gas mixture is 271 ^oC, calculate the average kinetic energy (in J mol^-1) of the H₂ molecules and O₂ molecules.

Answer 1

Average kinetic energy of a gas do not depend on the identity of the gas. It depends only on the temperature.

Average kinetic energy = 3RT/2

where,

R = gas constant = 8.314 J/mol.K

T = temperature of the gas = 271 ^oC = (271 + 273) K = 544 K

Hence, the average kinetic energy = (3 x 8.314 J/mol.K x 544 K)/2

   = 6784 J/mol         

Therefore, the average kinetic energy of the H₂ and O₂ molecules = 6784 J/mol