Question

how many liters of oxygen are required to react completely with 3.6 liters of hydrogen to form water?

how do i do this problem... thanks:)

Answer 1

2H2+3FeO-->3Fe +Al2O3.

Answer 2

You can't make aluminum out of hydrogen.

In answer to your original question, volumes are proportional to moles, when Pressure and Temperature are constant. You need half as many moles of O2 as you do H2, when H2O is being made in the reaction
2 H2 + O2 = 2 H2O
The answer is therefore 1.8 liters.