IB Chemistry SL Reactivity 1.3 Energy from Fuels

Practise balancing combustion and fuel-cell equations, comparing fossil and renewable fuels, and evaluating energy output, emissions and land use.

Syllabus
First assessment 2025
Topic
1.3
Level
SL

Exam points

  • balance complete or incomplete combustion equations and calculate oxygen or product mole ratios
  • compare fossil and biofuel choices using energy yield, emissions, renewability and land use
  • construct acidic or alkaline fuel-cell half-equations and combine them into an overall reaction

Covered syllabus points

1.3.1—Combustion reactions1.3.2—Incomplete combustion1.3.3—Fossil fuels1.3.4—Biofuels1.3.5—Fuel cells

1.3 Energy from fuels question 1

[Maximum number: 1]

Ethyne, C2H2\mathrm{C}_{2} \mathrm{H}_{2}, reacts with oxygen in welding torches.

Write an equation for the complete combustion of ethyne.

1.3 Energy from fuels question 2

[Maximum number: 1]

Which products may be formed during incomplete combustion of octane?

A

CO2\mathrm{CO}_{2} and H2\mathrm{H}_{2}

B

CO and H2\mathrm{H}_{2}

C

CO and H2O\mathrm{H}_{2} \mathrm{O}

D

C, CO and H2\mathrm{H}_{2}

1.3 Energy from fuels question 3

[Maximum number: 3]

Gasoline (petrol), biodiesel and ethanol are fuels.

Table for Question 1.3 Energy from fuels question 3 — IB Chemistry SL

Question (a)

(a)

A mixture of gasoline and ethanol is often used as a fuel. Suggest an advantage of such a mixture over the use of pure gasoline. Exclude any discussion of cost.

[ 1 ]

Question (b)

(b)

Methane is another greenhouse gas. Contrast the reasons why methane and carbon dioxide are considered significant greenhouse gases.

[ 2 ]
All question bank results loaded