If number of molecules of H₂ are double than that of O₂ , the ratio of kinetic energy of hydrogen and that of oxygen at 300K is

The average kinetic energy translation per molecule of all gases is same for all gases at same temperature and is given by,
K.E. = 3/2 kT

- Hence for hydrogen molecules
K.E.(H2) = 3/2 kT
K.E.(O2) = 1.5×1.380×300 = 621J

- Also for oxygen molecules
K.E.(O2) = 3/2 kT
K.E.(O2) = 1.5×1.380×300 = 621J

K.E.(H2)/K.E.(O2) = 621/621 = 1
- Therefore, Ratio of hydrogen to oxygen is 1.