Question

24 (i) State whether the following statements are true or false.

LPG and CNG burn using oxygen gas and release carbon dioxide gas.

• A. True
• B. False

Answer 1

The correct option is A True

Combustion reactions always occur in the presence of Oxygen.

Part 1: CNG (Compressed Natural Gas) contains methane $\left({\mathrm{CH}}_4\right)$

The burning of methane releases Carbon dioxide and water.

$\underset{\mathrm{Methane}}{{\mathrm{CH}}_4\left(\mathrm{g}\right)}+\underset{\mathrm{Oxygen}}{2{\mathrm{O}}_2(\mathrm{g}})\to \underset{\mathrm{Carbon}\mathrm{dioxide}}{{\mathrm{CO}}_2\left(\mathrm{g}\right)}+\underset{\mathrm{Water}}{2{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)}$

Part 2: LPG (Liquified Petroleum Gas) contains propane $\left({\mathrm{C}}_3{\mathrm{H}}_8\right)$ and butane $\left({\mathrm{C}}_4{\mathrm{H}}_{10}\right)$

$\underset{\mathrm{Propane}}{{\mathrm{C}}_3{\mathrm{H}}_8\left(\mathrm{g}\right)}+\underset{\mathrm{Oxygen}}{5{\mathrm{O}}_2\left(\mathrm{g}\right)}\to \underset{\mathrm{Carbon}\mathrm{dioxide}}{3{\mathrm{CO}}_2\left(\mathrm{g}\right)}+\underset{\mathrm{Water}}{4{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)}$

Hence, the products of complete combustion of CNG and LPG are mainly produced ${\mathrm{CO}}_2$ and ${\mathrm{H}}_2\mathrm{O}$

Final answer: The given statement is true.