How does the number of molecules in 1 mol of oxigen compare with the number of molecules in 1 mol of nitrogen?

They are the same.

Explanation:

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In this case, according to the Avogadro's number, we take into account that for molecules such as gaseous oxygen (O₂) and nitrogen (N₂), we realize that 1 mole of these contain 6.022x10²³ moles of molecules; as we are given  1 mol each, we notice they both have 6.022x10²³ molecules, therefore, they number of molecules is the same because they have the same number of moles.

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