In the reaction #H_2S + 2O_2 -> H_2SO_4#, the law of definite proportions predicts that for every mole of #H_2S#, you will need how many moles of #O_2#?
Clearly it is 2 moles.
I would look at your equation again. You have even balanced and formatted it properly. What does it say? It says 1 molecule of hydrogen sulfide reacts with 2 molecules of oxygen to make 1 molecule of sulfuric acid.
What is the relationship between molecules and moles? A mole is simply Avogadro's number of molecules, a very large number, i.e.
Please note that sulfuric acid is not produced in this way (from so-called conc. sour gas which sends the environmentalists screaming), and I doubt hydrogen sulfide can be oxidized up to to sulfuric acid easily.