Reactivity 1.3.1 - Reactive metals, non-metals and organic compounds undergo combustion reactions when heated in oxygen.

• Deduce equations for reactions of combustion, including hydrocarbons and alcohols.

Guidance

Tools and links

• Reactivity 2.2 - Why is high activation energy often considered to be a useful property of a fuel?
• Reactivity 3.2 - Which species are the oxidizing and reducing agents in a combustion reaction?

Reactivity 1.3.2 - Incomplete combustion of organic compounds, especially hydrocarbons, leads to the production of carbon monoxide and carbon.

• Deduce equations for the incomplete combustion of hydrocarbons and alcohols.

Guidance

Tools and links

• Inquiry 2 - What might be observed when a fuel such as methane is burned in a limited supply of oxygen?
• Reactivity 2.1 - How does limiting the supply of oxygen in combustion affect the products and increase health risks?

Reactivity 1.3.3 - Fossil fuels include coal, crude oil and natural gas, which have different advantages and disadvantages.

• Evaluate the amount of carbon dioxide added to the atmosphere when different fuels burn.
• Understand the link between carbon dioxide levels and the greenhouse effect.

Guidance

• The tendency for incomplete combustion and energy released per unit mass should be covered.

Tools and links

• Structure 3.2 - Why do larger hydrocarbons have a greater tendency to undergo incomplete combustion?
• AHL Structure 3.2 - Why is carbon dioxide described as a greenhouse gas?
• Nature of science, Reactivity 3.2 - What are some of the environmental, economic, ethical and social implications of burning fossil fuels?

Reactivity 1.3.4 - Biofuels are produced from the biological fixation of carbon over a short period of time through photosynthesis.

• Understand the difference between renewable and non-renewable energy sources.
• Consider the advantages and disadvantages of biofuels.

Guidance

• The reactants and products of photosynthesis should be known.

Tools and links

Reactivity 1.3.5 - A fuel cell can be used to convert chemical energy from a fuel directly to electrical energy.

• Deduce half-equations for the electrode reactions in a fuel cell.

Guidance

• Hydrogen and methanol should be covered as fuels for fuel cells.
• The use of proton exchange membranes will not be assessed.

Tools and links

• Reactivity 3.2 - What are the main differences between a fuel cell and a primary (voltaic) cell?