1. 1
   A shipping company burns heavy fuel oil in its cargo ship engines and wants to understand which pollutant produced by this combustion is described as a toxic, colourless, odourless gas that is especially dangerous in enclosed spaces such as engine rooms.

   (a)

   Which pollutant is this?

   [1 mark]

   • ACarbon monoxide
   • BSulfur dioxide
   • CWater vapour
   • DCarbon dioxide

   (b)

   The shipping company's engineers also test the exhaust gases for a pollutant that reacts with water vapour in the atmosphere to form acid rain, and which is produced when sulfur impurities in the heavy fuel oil are burned. Which pollutant is this?

   [1 mark]

   • ACarbon monoxide
   • BSulfur dioxide
   • CParticulates
   • DUnburned hydrocarbons

   (c)

   The shipping company also detects solid particulates in the exhaust from its engines. Describe one problem caused by particulates released into the atmosphere, and explain briefly why particulates are produced during the combustion of heavy fuel oil.

   [2 marks]

   Total for question 1: 4 marks

2. 2
   A city planning department is investigating why oxides of nitrogen are found in high concentrations near a busy motorway junction.

   (a)

   Under which condition are oxides of nitrogen most likely to form during the combustion of fuel in vehicle engines?

   [1 mark]

   • AOnly when the engine is running at a very low temperature
   • BOnly when the fuel itself contains dissolved nitrogen compounds
   • CAt the high temperatures reached inside an engine, causing nitrogen and oxygen from the air to react
   • DOnly during the refining of crude oil into petrol, not during combustion

   (b)

   The planning department is also concerned about the health effects on residents living close to the motorway. Which health problem is commonly associated with high concentrations of oxides of nitrogen and sulfur dioxide in the air?

   [1 mark]

   • AImproved lung function
   • BTooth decay
   • CVitamin D deficiency
   • DRespiratory problems

   (c)

   The planning department is preparing a report and needs to list, in full, the main atmospheric pollutants produced by burning fuels in vehicle engines, along with one problem caused by each. Give three different pollutants (other than oxides of nitrogen) produced by combustion of fuels, and state one problem associated with each.

   [2 marks]

   Total for question 2: 4 marks

3. 3
   A furniture manufacturer is preparing a life cycle assessment (LCA) for a new wooden chair, comparing a version made from imported hardwood with a version made from locally sourced pine, in order to estimate the carbon footprint of each.

   (a)

   Describe the four stages of a life cycle assessment that the manufacturer should consider when comparing the two chair designs.

   [3 marks]

   (b)

   A rival furniture company claims that its own LCA proves its chairs are more environmentally friendly than any competitor's, based on a short summary that only reports energy used during manufacturing. Explain why this claim should be treated with caution, referring to the objectivity of life cycle assessments and how LCAs can be misused.

   [4 marks]

   Total for question 3: 7 marks

4. 4
   A national environment agency is preparing new regulations to reduce both the carbon footprint of industry and the release of atmospheric pollutants from fuel combustion across the country. An industry association objects, arguing that a full life cycle assessment of switching to cleaner fuels would show a smaller environmental benefit than the agency claims.

   (a)

   Explain what is meant by carbon footprint, describe the range of atmospheric pollutants produced by burning fuels and the specific problems each causes, and discuss why actions to reduce carbon dioxide and methane emissions, and other pollutants, may be limited in practice for industry.

   [6 marks]

   (b)

   An industry association objects to the proposed regulations, arguing that a full life cycle assessment of switching to cleaner fuels would show the environmental benefit is smaller than the agency claims, once the emissions from manufacturing new cleaner equipment are also included. Evaluate this argument, discussing how a proper life cycle assessment should be carried out, why LCAs are not always purely objective, and how the environment agency could respond to ensure a fair and balanced comparison is made before finalising the regulations.

   [6 marks]

   Total for question 4: 12 marks

End of questions