Two rigid containers of equal volume hold hydrogen and argon gases respectively at the same temperature and pressure. Which of the following statements is(are) false ?

A) The two containers hold an equal mass of gas.
B) The two containers hold an equal number of gas particles.
C) The molecules in each container have the same average kinetic energy.
D) The two containers hold an equal number of atoms.
E) The two containers hold an equal number of moles of gas.

1 answer

Think about this.
PV = nRT for each gas, therefore, if we solve for n = PV/RT then
(PV/RT)<Ar = (PV/RT)H2. Then, since
n = grams/molar mass, we can write
(PV/RT)Ar = (PV/RT)H2 = (g/MM)Ar = (g/MM)H2. Since P, V, R, and T are the same, we can dispense with the PV/RT and just write
(g/MM)Ar = (g/MM)H2.