Answer: A The number of molecules in the hydrogen container is the same as the number of molecules in the oxygen container.
D The average speed of the hydrogen molecules is the same as the average speed of the oxygen molecules.
Explanation:
A. According to avogadro's law, 1 mole of every substance occupies 22.4 L at NTP, weighs equal to the molecular mass and contains avogadro's number of particles.
Thus oxygen will have more molecules as it has more moles.
B. Density is defined as the mass contained per unit volume.
As volume is same, density depends on mass. As mass of hydrogen is less, its density will also be less.
C. Average kinetic energy is defined as the average of the kinetic energies of all the particles present in a system. It is determined by the equation:
Thus at same temperature, the average kinetic energy of the hydrogen molecules is the same as the average kinetic energy of the oxygen molecules.
D. The formula for average speed is :
Thus as molecular mass of hydrogen is less than that of oxygen , the average speed of hydrogen will be more than that of oxygen.