Question

1 mole of Hydrocarbon requires a maximum volume of oxygen for complete combustion under the same condition. Identify the hydrocarbon.

• A. ${\mathrm{CH}}_4$
• B. ${\mathrm{C}}_2{\mathrm{H}}_6$
• C. ${\mathrm{C}}_3{\mathrm{H}}_6$
• D. ${\mathrm{C}}_4{\mathrm{H}}_8$

Answer 1

The correct option is D

${\mathrm{C}}_4{\mathrm{H}}_8$

The explanation for the correct option:

The combustion of hydrocarbon fuels releases carbon dioxide$\left({\mathrm{CO}}_2\right)$, as well as other greenhouse gases that contribute to atmospheric pollution and climate change.

(D) Butene is an organic chemical compound with a chemical formula${\mathrm{C}}_4{\mathrm{H}}_8$. At standard temperature and pressure, ethane is a colorless, odorless gas. The complete combustion of Butene releases heat and produces carbon dioxide and water.

• Reaction: $\underset{Butene}{{\mathrm{C}}_4{\mathrm{H}}_8}\left(g\right)+\underset{\mathrm{Oxygen}}{6{\mathrm{O}}_2\left(\mathrm{g}\right)}\to \underset{\mathrm{Carbon}\mathrm{dioxide}}{4{\mathrm{CO}}_2\left(\mathrm{g}\right)}+\underset{\mathrm{Water}}{4{\mathrm{H}}_2\mathrm{O}}\left(\mathrm{l}\right)+\mathrm{Heat}$
• In this reaction for complete combustion of 1 mole of ${\mathrm{C}}_4{\mathrm{H}}_8$, 6 moles of ${\mathrm{O}}_2$ is required.

The explanation for the incorrect option:

The combustion of hydrocarbon fuels releases carbon dioxide$\left({\mathrm{CO}}_2\right)$, as well as other greenhouse gases that contribute to atmospheric pollution and climate change.

(A) Methane is an organic chemical compound with a chemical formula${\mathrm{CH}}_4$. At standard temperature and pressure, ethane is a colorless, odorless gas. The complete combustion of Methane releases heat and produces carbon dioxide and water.

• Reaction: $\underset{\mathrm{Methane}}{{\mathrm{CH}}_4\left(\mathrm{g}\right)}+\underset{\mathrm{Oxygen}}{2{\mathrm{O}}_2\left(\mathrm{g}\right)}\to \underset{\mathrm{Carbon}\mathrm{dioxide}}{{\mathrm{CO}}_2\left(\mathrm{g}\right)}+\underset{\mathrm{Water}}{2{\mathrm{H}}_2\mathrm{O}\left(\mathrm{g}\right)}+\mathrm{Heat}$
• In this reaction for complete combustion of 1 mole of ${\mathrm{CH}}_4$, 2 moles of ${\mathrm{O}}_2$ is required.

(B) Ethane is an organic chemical compound with a chemical formula${\mathrm{C}}_2{\mathrm{H}}_6$. At standard temperature and pressure, ethane is a colorless, odorless gas. The complete combustion of Ethane releases heat and produces carbon dioxide and water.

• Reaction: $\underset{\mathrm{Ethane}}{2{\mathrm{C}}_2{\mathrm{H}}_6}\left(g\right)+\underset{\mathrm{Oxygen}}{7{\mathrm{O}}_2}\left(\mathrm{g}\right)\to \underset{\mathrm{Carbon}\mathrm{dioxide}}{4{\mathrm{CO}}_2\left(\mathrm{g}\right)}+\underset{\mathrm{Water}}{6{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)}+\mathrm{Heat}$
• In this reaction for complete combustion of 2 moles of ${\mathrm{C}}_2{\mathrm{H}}_6$, 7mole moles of ${\mathrm{O}}_2$ is required. Therefore, for 1 mole of ${\mathrm{C}}_2{\mathrm{H}}_6$, 3.5 mole moles of ${\mathrm{O}}_2$ is required.

(C) Propene is an organic chemical compound with a chemical formula${\mathrm{C}}_3{\mathrm{H}}_6$. At standard temperature and pressure, ethane is a colorless, odorless gas. The complete combustion of Propene releases heat and produces carbon dioxide and water.

• Reaction: $\underset{Propene}{2{\mathrm{C}}_3{\mathrm{H}}_6}\left(g\right)+\underset{\mathrm{Oxygen}}{9{\mathrm{O}}_2\left(\mathrm{g}\right)}\to \underset{\mathrm{Carbon}\mathrm{dioxide}}{6{\mathrm{CO}}_2\left(\mathrm{g}\right)}+\underset{\mathrm{Water}}{6{\mathrm{H}}_2\mathrm{O}}\left(\mathrm{l}\right)+\mathrm{Heat}$
• In this reaction for complete combustion of 2 moles of ${\mathrm{C}}_3{\mathrm{H}}_6$, 9 moles of ${\mathrm{O}}_2$ is required. Therefore, for combustion of 1 mole of ${\mathrm{C}}_3{\mathrm{H}}_6$, 4.5 mole of ${\mathrm{O}}_2$ is required.

Thus, option (C) i.e., ${\mathrm{C}}_4{\mathrm{H}}_8$ requires a maximum volume of oxygen for complete combustion under the same condition.