Question

What volume of oxygen gas ($O_2$) measured at $0^{o}C$ and 1 atm, is needed to burn completely 1 L of propane gas $\left(C_3{H}_8\right)$ measured under the same conditions ?

• A. 5 L
• B. 10 L
• C. 7 L
• D. 6 L

Answer 1

The correct option is A 5 L

In a balanced chemical reaction, for the combustion of propane, volume of oxygen and propane required is:

$\underset{1L}{\underset{1vol.}{C_3{H}_8\left(g\right)}}+\underset{5L}{\underset{5vol.}{5O_2\left(g\right)}}\to \underset{3L}{\underset{\text{3 vol.}}{2C{O}_2\left(g\right)}}+\underset{4L}{\underset{4vol.}{4H_{2}O\left(g\right)}}$

Hence volume of oxygen gas measured at $0^{o}C$ and $1atm,$ ineeded to burn completely $1L$ of propane gas $\left(C_3{H}_8\right)$ under the same conditions is $5L$.