Which of the gases contains the same number of molecules as that of 16 g oxygen?

7g of nitrogen contains the same number of molecules as

Which contains the same number of molecules as 16 g oxygen

Which contains the same number of molecules as 16 g of oxygen :

Which of the following contains the same number of molecules ?

Which of the following contains the same number of molecules ?

Which of the following contains the same number of molecules ?

The mixture containing the same number of molecules as that of 14 g of CO is

What is the mass of carbon dioxide which contains the same number of molecules as are contained in 40 g of oxygen?