Deduce the balanced equation for the complete combustion of propan-1-ol. State symbols are not required.

State one visible observation that may indicate incomplete combustion.

Write a balanced equation for the incomplete combustion of butane to form carbon monoxide and water.

Explain why carbon monoxide is a health risk.

State the equation for photosynthesis.

Outline why ethanol from plants may have a lower net carbon footprint than a petroleum fuel.

Calculate the experimental energy released per gram of ethanol using $q=mc\Delta T$. Assume the density of water is $1.00\ \text{g cm}^{-3}$ and the specific heat capacity of water is $4.18\ \text{J g}^{-1}\ \text{K}^{-1}$.

Deduce the balanced equation for the complete combustion of ethanol.

Suggest one reason why the experimental value is less exothermic than the data book value for ethanol.

Deduce the half-equation at the anode.

Deduce the overall cell reaction from the two electrode half-equations.

State one difference between a fuel cell and a primary voltaic cell.

Calculate the mass of $CO_2$ produced per $1.00\ MJ$ of energy released by methane, using $\Delta H_c^\theta = -891\ kJ\ mol^{-1}$.

Propane releases $2220\ kJ\ mol^{-1}$ and produces three moles of $CO_2$ per mole of propane. Calculate the mass of $CO_2$ produced per $1.00\ MJ$ of energy released by propane, and state which fuel releases less $CO_2$ per unit energy.

Deduce the half-equation at the anode.

Deduce the half-equation at the cathode.

State two differences between a fuel cell and a primary voltaic cell.

State the type of radiation absorbed by greenhouse gases such as $CO_2$.

Explain, in molecular terms, why $CO_2$ is a greenhouse gas but $N_2$ and $O_2$ are not significant greenhouse gases.

State which hydrocarbon, methane or octane, has the greater tendency to undergo incomplete combustion.

Explain this tendency in terms of intermolecular forces and mixing with oxygen.

Deduce the anode half-equation for the acidic methanol fuel cell.

Deduce the cathode half-equation using six electrons.

Deduce the overall cell reaction and state one environmental disadvantage of using methanol in this fuel cell.

Define activation energy.

Explain why a relatively high activation energy is a useful property of a fuel.

Describe the effect of decreasing the air supply on the products of combustion.

Deduce the balanced equation for incomplete combustion of propane forming carbon monoxide and water only.

Explain why operating the burner with very low air supply increases health risk.

Identify the fuel in the table that releases the least $CO_2$ per unit energy when burned completely.

Calculate the mass of $CO_2$ released per $MJ$ of energy when propane is burned completely.

Evaluate why the fuel with the lowest direct $CO_2$ emission per unit energy may still not be the best choice in all situations.

State the reactants and products of photosynthesis.

Using the data, calculate the net life-cycle emission for sugarcane ethanol.

Suggest one disadvantage of using the crop-based biofuel shown by the data.

Identify the radiation region in which $CO_2$ absorbs most strongly in relation to Earth’s emitted radiation.

Explain how this absorption contributes to the greenhouse effect.

Suggest why increasing the concentration of $CO_2$ changes the energy balance even though $CO_2$ is a minor component of air.

Describe the relationship between carbon chain length and soot formation shown by the data.

Explain why larger hydrocarbons have a greater tendency to undergo incomplete combustion under these conditions.

Suggest one change to the burner that would reduce carbon monoxide and soot formation.

Using the data, calculate the mass of $CO_2$ emitted per $MJ$ of energy released for coal, using $24\ MJ\ kg^{-1}$ and $2.40\ kg$ $CO_2$ per $kg$ fuel.

Natural gas releases $50\ MJ\ kg^{-1}$ and produces $2.75\ kg$ $CO_2$ per $kg$ fuel. Calculate the mass of $CO_2$ emitted per $MJ$ of energy released for natural gas.

Evaluate one advantage and one limitation of choosing natural gas rather than coal.

State the process by which maize plants convert atmospheric carbon dioxide into organic compounds.

Explain why the combustion of ethanol does not by itself prove that the fuel is carbon neutral.

Discuss two life-cycle factors that could make the net greenhouse gas emissions of the biofuel higher than claimed.

Determine the change in oxidation state of carbon when methanol, $CH_3OH$, is converted to $CO_2$ in the fuel cell.

The anode reaction is $CH_3OH(aq)+H_2O(l)\to CO_2(g)+6H^+(aq)+6e^-$. Deduce the cathode half-equation and the overall reaction.

Using the data, explain one advantage and one disadvantage of methanol compared with compressed hydrogen for the portable power unit.

Using the data, identify two gases that are significant infrared absorbers in the terrestrial infrared region.

Explain why $N_2$ and $O_2$ are not significant greenhouse gases, using the molecular information.

Carbon dioxide is linear and non-polar overall. Suggest why it can still absorb infrared radiation.

Describe two trends shown by the data.

Explain how combustion of fossil fuels can lead to an increase in atmospheric $CO_2$ concentration.

Evaluate whether the graph alone proves that increasing $CO_2$ is the only cause of the observed temperature change.

Deduce the balanced equation for the complete combustion of butan-1-ol, $C_4H_9OH(l)$, forming liquid water.

Explain why the complete combustion of butan-1-ol is exothermic in terms of bond breaking and bond forming.

Explain two observations expected when propane burns in a limited supply of oxygen.

Discuss why the use of the stove in a poorly ventilated space is hazardous.

Compare and contrast a hydrogen fuel cell with a primary voltaic cell.

Explain why a hydrogen fuel cell may be described as clean at the point of use but not necessarily carbon-free over its life cycle.

Calculate the total $CO_2$ equivalent emission per kilometre for hydrogen made by methane reforming and used in a fuel cell, using the upstream and use-phase data.

Explain why the statement “a hydrogen fuel cell vehicle produces no carbon dioxide” is incomplete.

Evaluate which option in the table gives the best overall environmental outcome. Use two pieces of evidence from the data.

Calculate the net annual change in greenhouse gas emissions for the project relative to continued petrol use.

Explain why bioethanol cannot automatically be described as carbon neutral.

Using the figure, state one social or ethical concern that should be considered before approving the project.

Explain why octane has a greater tendency than methane to undergo incomplete combustion in an engine.

Evaluate whether methane is the best fuel of the three for the heater, using both chemical and practical considerations.

Explain why ethanol made from sugar cane may have a lower net carbon footprint than petrol, but should not automatically be described as carbon neutral.

Evaluate one environmental advantage and one social or ethical disadvantage of replacing petrol with ethanol from food crops.

Discuss one advantage and two disadvantages of methanol as a fuel for a vehicle fuel cell compared with hydrogen.

Suggest why fuel cells can be more efficient than engines that first burn a fuel to produce heat.

Contrast the significance of carbon dioxide and methane as greenhouse gases.

Explain why replacing coal-fired power stations with natural gas can reduce, but not eliminate, climate impact.

Analyse why the tendency to form soot increases from hexane to hexadecane under the same flame conditions.

Evaluate one benefit and one limitation of using shorter-chain hydrocarbons as engine fuels.

Analyse why methane releases less carbon dioxide than ethanol for the same heat release in this comparison, even though ethanol is a biofuel when produced from biomass.

Explain how increased atmospheric carbon dioxide contributes to the greenhouse effect.

Compare the operation of a fuel cell with direct combustion of hydrogen in oxygen.

Evaluate whether hydrogen fuel-cell vehicles should be described as zero-emission vehicles.

Explain why natural gas generally releases less carbon dioxide per unit energy than coal.

Evaluate the environmental, economic and ethical implications of replacing coal with natural gas rather than moving directly to renewable energy.

Deduce the overall equation for a methanol fuel cell and use it to identify one point-of-use environmental disadvantage relative to a hydrogen fuel cell.

Discuss which energy carrier is most suitable for the island community. Consider reliability, storage and environmental impact.