Answer:
62L
Step-by-step explanation:
2 H2(g) + O2(g) → 2 H2O(g)
From the stoichiometry of the balanced equation;
2 mol of H2 reacts with 1 mol of O2.
From the law of combining volumes, equal moles of gases occupies equal volume.
This means;
2 L of H2 reacts with 1 L of O2
x L of hydrogen reacts with 31 L of O2
2 = 1
x = 31
Solving for x;
x = 62 L