What exact volume of oxygen gas ($\mathrm{O}_2$) measured at $0^{\circ}\mathrm{C}$ and $1 \mathrm{~a

Question

What exact volume of oxygen gas ($\mathrm{O}_2$) measured at $0^{\circ}\mathrm{C}$ and $1 \mathrm{~atm}$ is fundamentally needed to burn completely $2 \mathrm{~L}$ of butane gas ($\mathrm{C}_4\mathrm{H}_{10}$) measured under identical conditions?

Professor PC Thomas Classes · Answer

(a) : The balanced chemical equation for the combustion of butane is $\mathrm{C}_4\mathrm{H}_{10} + 6.5\mathrm{O}_2 ightarrow 4\mathrm{CO}_2 + 5\mathrm{H}_2\mathrm{O}$. According to Gay-Lussac's law of combining volumes, gases react in simple whole-number volume ratios. Here, 1 volume (or $1 \mathrm{~L}$) of butane requires exactly $6.5 \mathrm{~L}$ of oxygen. Therefore, $2 \mathrm{~L}$ of butane will require $2 	imes 6.5 = 13 \mathrm{~L}$ of oxygen.