You are given a container of 1 mole of helium gas (He), and an identical container of 1 mole of oxygen gas ...

Question

You are given a container of 1 mole of helium gas (He), and an identical container of 1 mole of oxygen gas (O2). Both gases are at STP. Which statements are true or false:

a) both gas samples have the same number of particles (molecules)
b) both gas samples have the same number of atoms
c) Both samples have the same mass
d) Both samples have the same density
e) both samples have the same average kinetic energy
f) the particles of both samples have the same average speed
g) if there was an identical pinhole in both containers, both samples would efuse at the same time
h) The actual volume occupied by the gas particles is the same for both samples
i) both are ideal gases.

Answer 1

I would say that some are really NOT good questions. But I will try to answer them faithfully.
a) both gas samples have the same number of particles (molecules)
(approximately) Yes.
b) both gas samples have the same number of atoms
Definitely No.
c) Both samples have the same mass
Definitely No.
d) Both samples have the same density
Definitely No.
e) both samples have the same average kinetic energy
Helium molecules only have translational kinetic energy (3 degrees of freedom), while O2 molecules can have both translational kinetic energy (3 degrees of freedom), as well as rotational kinetic energy (2 degrees of freedom). So the answer is: No.
f) the particles of both samples have the same average speed
Definitely No.
g) if there was an identical pinhole in both containers, both samples would efuse at the same time.
Of course both gas would efuse as long as there is a pinhole in both containers, and the efusion can occur at the same time! But if the statement would change to: "if there was an identical pinhole in both containers, both samples would efuse at the same rate", the answer then would be "No".
h) The actual volume occupied by the gas particles is the same for both samples.
If you are talking about the container volume, the answer would be "Yes". But if you are talking about the volume of individual molecule, then answer would be "No".
i) both are ideal gases.
No real gas can be ideal gas strictly. However, both can be approximated as ideal gases under the specified condition, with Helium in a better approximation.

Answer 2

I am garee with your answer. It could be A.