What volume of propane consumes one litre of oxygen during its complete combustion?
0.2 L of propane is required for every litre of oxygen consumed.
The balanced equation is
According to Gay-Lussac's Law of Combining volumes, the ratios of the volumes are the same as the ratios of the molecules (the coefficients in the balanced equation).
∴ 0.2 L of propane is required for every litre of oxygen consumed.