Question

Assuming all volume measurements are made at the same temperature and pressure, how many liters of oxygen gas would it take to react completely with 7.25 liters of hydrogen gas? show all of the work used to solve this problem. balanced equation: 2h2 (g) + o2 (g) yields 2h2 o(g)

Answer 1

You don't have to worry about converting to moles and back to liters. You need to know about Gay-Lussac's law of combining volumes. Coupled with Avogadro's law which says that the moles of gas are proportional to the volume, all we have to do is:

2H2(g) + O2(g) -> 2H2O(g)
2L ..........1L ..........2L
7.25L .....3.63L .....7.25L

The only work is dividing 7.25 by 2.