If a Liter of CO₂ Is Compared to a Liter

If a liter of CO₂ is compared to a liter of H₂, both at 25°C and one atmosphere pressure, then:

A) the CO₂ and H₂ molecules have the same average speed
B) there are more H₂ molecules than CO₂ molecules
C) the average kinetic energy of the CO₂ molecules is greater than that of the H2 molecules
D) the CO₂ molecules are, on the average, moving more slowly than the H₂ molecules
E) the mass of one liter of CO₂ equals the mass of one liter of H₂