• Syllabus

C: Energy

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Sub sections and their related questions

C.1 Energy sources

• 16M.3.sl.TZ0.11b: (i) Octane, C8H18, can undergo complete combustion under suitable conditions. Calculate the...
• 16N.3.sl.TZ0.11a: (i) Calculate the specific energy of the lithium ion battery, in MJ kg−1, when 80.0 kg of fuel in...
• 16N.3.sl.TZ0.11b: (i) The energy density of gasoline is 34.3 MJ dm−3. Calculate the volume of gasoline, in dm3,...
• 17M.3.sl.TZ1.15c: Explain, in terms of the molecular structure, the critical difference in properties that makes...
• 17M.3.sl.TZ1.15d: Determine the specific energy, in kJ\(\,\)g−1, and energy density, in kJ\(\,\)cm−3, of a...
• 17M.3.sl.TZ2.13a: State one advantage and one disadvantage for each energy source in the table.
• 17M.3.sl.TZ2.13b.i: Calculate the specific energy of hydrogen, stating its units. Refer to sections 1, 6 and 13 of...
• 17M.3.sl.TZ2.13b.ii: Hydrogen has a higher specific energy than petrol (gasoline) but is not used as a primary fuel...
• 17N.3.sl.TZ0.12a: Calculate the specific energy of octane, C8H18, in kJ kg–1 using sections 1, 6 and 13 of the data...
• 17N.3.sl.TZ0.12b: A typical wood has a specific energy of 17 × 103 kJ kg–1. Comment on the usefulness of octane and...
• 17N.3.sl.TZ0.12c: State the name of one renewable source of energy other than wood.
• 18M.3.sl.TZ1.10c.i: Determine the specific energy and energy density of petrol (gasoline), using data from sections 1...
• 18M.3.sl.TZ1.10c.ii: Outline why the energy available from an engine will be less than these theoretical values.
• 18M.3.sl.TZ2.10a: Outline two reasons why oil is one of the world’s significant energy sources.
• 18M.3.sl.TZ2.12a: Calculate the thermal efficiency of a steam turbine supplied with steam at 540°C and using a...
• 18M.3.sl.TZ2.12b: Power plants generating electricity by burning coal to boil water operate at approximately 35%...

C.2 Fossil fuels

• 15M.3.sl.TZ2.11a: Suggest two reasons for this shift.
• 14M.3.sl.TZ1.8a: Suggest why crude oil needs to be refined before it can be used.
• 14M.3.sl.TZ1.8c: Thermal cracking, catalytic cracking and steam cracking can all be used to convert molecules of...
• 13M.3.sl.TZ1.C2a: The following reaction occurs during the cracking of tetradecane,...
• 13M.3.sl.TZ1.C2b: State the main type of product obtained from steam cracking.
• 12N.3.sl.TZ0.C2: the oil industry surplus long-chain hydrocarbons are converted into shorter, more useful...
• 10N.3.sl.TZ0.C1: “Oil should not be used as a source of energy because it has more important uses.” Suggest...
• 10N.3.sl.TZ0.C2: Thermal cracking, catalytic cracking and steam cracking are all used to convert alkane molecules...
• 11M.3.sl.TZ1.C2a: The initial products of the fractional distillation of oil often undergo cracking. This can be...
• 11M.3.sl.TZ2.C2d.i: Identify the catalyst used in the catalytic cracking of long chain hydrocarbons and state one...
• 11M.3.sl.TZ2.C2d.ii: State an equation for the catalytic cracking of the straight chain hydrocarbon pentadecane,...
• 12M.3.sl.TZ1.C3a: Name two fuels that are obtained from petroleum.
• 12M.3.sl.TZ1.C3b: Describe one environmental problem that can result from the combustion of these fuels in the...
• 12M.3.sl.TZ1.E1b: Suggest why carbon dioxide is the greenhouse gas most frequently connected with the effect of...
• 16M.3.sl.TZ0.11a: (i) Hexane can be converted to different organic products in a reforming process. Identify one of...
• 16M.3.sl.TZ0.11c: Coal can be heated with steam to produce synthetic natural gas. Formulate an equation to show the...
• 16N.3.sl.TZ0.12a: Discuss how the octane number changes with the molecular structure of the alkanes.
• 16N.3.sl.TZ0.12b: Catalytic reforming and cracking reactions are used to produce more efficient fuels. Deduce the...
• 17M.3.sl.TZ1.16a: State how these gases are produced, giving the appropriate equation(s).
• 17M.3.sl.TZ1.16b: Outline how the carbon monoxide is then converted to a hydrocarbon fuel.
• 17M.3.sl.TZ2.14c.i: Suggest an equation for the production of syngas from coal.
• 17M.3.sl.TZ2.14c.ii: The Fischer-Tropsch process, an indirect coal liquefaction method, converts CO(g) and H2(g) to...
• 17M.3.sl.TZ2.14c.iii: Suggest a reason why syngas may be considered a viable alternative to crude oil.
• 17N.3.sl.TZ0.13a: “Knocking” in an automobile (car) engine can be prevented by increasing the octane number of the...
• 17N.3.sl.TZ0.13b: Many like to refer to our “carbon footprint”. Outline one difficulty in quantifying such a concept.
• 18M.3.sl.TZ1.10a: Identify an element, other than carbon and hydrogen, found at significant concentrations in...
• 18M.3.sl.TZ1.10b: Petroleum contains many hydrocarbons. Explain how these are separated by fractional distillation.
• 18M.3.sl.TZ2.10b.i: Formulate an equation for the cracking of C16H34 into two products with eight carbon atoms each.
• 18M.3.sl.TZ2.10b.ii: Identify, giving a reason, which product in (b)(i) could be used in petrol (gasoline).
• 18M.3.sl.TZ2.10c.i: Outline how higher octane fuels help eliminate “knocking” in engines.
• 18M.3.sl.TZ2.10c.ii: The performance of hydrocarbons as fuels can be improved by catalytic reforming. Outline how...

C.3 Nuclear fusion and fission

• 10N.3.sl.TZ0.E4a: State what is meant by the term high-level radioactive waste.
• 10N.3.sl.TZ0.E4b: (i)     Explain why high-level waste should not be disposed of by landfill or...
• 09N.3.sl.TZ0.E4c: High-level and low-level wastes are two types of radioactive waste. Compare the half-lives and...
• 10M.3.sl.TZ1.E2b: State the characteristics and sources of low-level nuclear waste.
• 10M.3.sl.TZ1.E2c: The disposal of nuclear waste in the sea is now banned in many countries. Discuss one method of...
• 10M.3.sl.TZ2.E2: (a)     State one source of low-level radioactive waste and one source of high-level radioactive...
• 16M.3.sl.TZ0.13a: Curium, \({}^{240}{\rm{Cm}}\), was synthesized by bombarding thorium nuclei,...
• 16M.3.sl.TZ0.13b: Uranium-235 has a half-life of 7.038×108 years. (i) Determine the time required for the mass...
• 16M.3.sl.TZ0.13c: Outline why an element such as thorium, Th, usually undergoes nuclear fission, whereas helium,...
• 16N.3.sl.TZ0.15a: (i) Explain why fusion, combining two smaller nuclei into a larger nucleus, releases vast amounts...
• 16N.3.sl.TZ0.15b: Radioactive phosphorus, 33P, has a half-life of 25.3 days. (i) Calculate 33P decay constant λ...
• 17M.3.sl.TZ1.14a: Outline how the spectra of light from stars can be used to detect the presence of carbon.
• 17M.3.sl.TZ1.14b.i: Deduce the identity of X.
• 17M.3.sl.TZ1.14b.ii: Outline why this reaction results in a release of energy.
• 17M.3.sl.TZ1.14c: Nuclear fusion reactors are predicted to become an important source of electrical energy in the...
• 17M.3.sl.TZ2.12a.i: One fusion reaction occurring in the sun is the fusion of deuterium, \({}_1^2H\), with tritium,...
• 17M.3.sl.TZ2.12a.ii: Explain why this fusion reaction releases energy by using section 36 of the data booklet.
• 17N.3.sl.TZ0.14a.i: Compare and contrast fission and fusion in terms of binding energy and the types of nuclei involved.
• 17N.3.sl.TZ0.14a.ii: Suggest two advantages that fusion has over fission.
• 17N.3.sl.TZ0.14b: The amount of 228Ac in a sample decreases to one eighth \(\left( {\frac{1}{8}} \right)\) of its...
• 18M.3.sl.TZ1.12a.ii: Explain how 235U fission results in a chain reaction, including the concept of critical mass.
• 18M.3.sl.TZ1.12b: Suggest one reason why there is opposition to the increased use of nuclear fission reactors.
• 18M.3.sl.TZ2.13a: Compare and contrast the process of nuclear fusion with nuclear fission.  
• 18M.3.sl.TZ2.13b: Dubnium-261 has a half-life of 27 seconds and rutherfordium-261 has a half-life of 81...

C.4 Solar energy

• 16M.3.sl.TZ0.12a: Transesterification reactions allow waste cooking oils to be converted to biofuels. Identify a...
• 16M.3.sl.TZ0.12b: Deduce the equation for the reaction that occurs assuming that the vegetable oil has the formula...
• 16N.3.sl.TZ0.14a: State the equation for the complete transesterification of the triglyceride given below with...
• 16N.3.sl.TZ0.14b: Outline why the fuel produced by the reaction in (a) is more suitable for use in diesel engines...
• 17M.3.sl.TZ1.15a: State two reagents required to convert vegetable oil to biodiesel.
• 17M.3.sl.TZ1.15b: Deduce the formula of the biodiesel formed when the vegetable oil shown is reacted with the...
• 17M.3.sl.TZ1.15c: Explain, in terms of the molecular structure, the critical difference in properties that makes...
• 17M.3.sl.TZ1.15d: Determine the specific energy, in kJ\(\,\)g−1, and energy density, in kJ\(\,\)cm−3, of a...
• 17M.3.sl.TZ2.12b: Coloured molecules absorb sunlight. Identify the bonding characteristics of such molecules.
• 17N.3.sl.TZ0.15a: State the structural feature of chlorophyll that enables it to absorb visible light.
• 17N.3.sl.TZ0.15b: Vegetable oils are too viscous for use as liquid fuels. Describe, using an equation, how a...
• 18M.3.hl.TZ1.13a: Outline the major technical problem affecting the direct use of vegetable oils as fuels...
• 18M.3.hl.TZ1.13b: State the formula of a fuel that might be produced from the vegetable oil whose formula is...
• 18M.3.sl.TZ1.11a.i: Outline the major technical problem affecting the direct use of vegetable oils as fuels in...
• 18M.3.sl.TZ1.11a.ii: State the formula of a fuel that might be produced from the vegetable oil whose formula is...
• 18M.3.sl.TZ1.11b: Outline why biofuels are considered more environmentally friendly, even though they produce more...
• 18M.3.sl.TZ2.14a: Deduce the equation for the transesterification reaction of pentyl octanoate, C7H15COOC5H11, with...
• 18M.3.sl.TZ2.14b: Outline why the ester product of this reaction is a better diesel fuel than pentyl octanoate.

C.5 Environmental impact—global warming

• 15M.3.hl.TZ2.22b.i: Describe on a molecular level how the greenhouse effect occurs.
• 15M.3.hl.TZ2.22b.ii: Suggest two factors that influence the relative greenhouse effect of a gas.
• 15M.3.sl.TZ2.19a.i: Water and carbon dioxide are greenhouse gases present in significant quantities in the...
• 15M.3.sl.TZ2.19a.ii: Suggest the two factors that influence the relative greenhouse effect of a gas.
• 14M.3.sl.TZ1.14a: Describe how these gases contribute to the greenhouse effect.
• 14M.3.sl.TZ1.14b: (i)     Identify by chemical formula one other greenhouse gas not mentioned above.   (ii)    ...
• 14M.3.sl.TZ1.14c: Many scientists claim that global warming is associated with the increasing concentration of...
• 14M.3.sl.TZ2.14: Suggest why the temperature decrease of the Earth’s surface after sunset is less when the weather...
• 14N.3.sl.TZ0.19a: Describe how the greenhouse effect causes the atmosphere of the Earth to increase in temperature.
• 14N.3.sl.TZ0.19b: Identify one greenhouse gas other than \({\text{C}}{{\text{O}}_{\text{2}}}\) and...
• 13M.3.sl.TZ1.E1a: Identify a gas that is both a greenhouse gas and a cause of ozone depletion.
• 13M.3.sl.TZ2.C1c: The worldwide production of aluminium by electrolysis makes a significant impact on global...
• 10N.3.sl.TZ0.A2b: Explain what happens at a molecular level during the absorption of IR radiation by carbon...
• 09N.3.sl.TZ0.E1a: Describe how carbon dioxide acts as a greenhouse gas.
• 09N.3.sl.TZ0.E1b: Discuss the influence of increasing amounts of greenhouse gases on the environment.
• 10M.3.sl.TZ2.A4: (a)     Explain why the nitrogen molecule, \({{\text{N}}_2}\), does not absorb infrared...
• 10M.3.sl.TZ2.E1: (a)     Major greenhouse gases are water vapour and carbon dioxide. State two other greenhouse...
• 09M.3.sl.TZ1.E1a: Two of the major greenhouse gases in the atmosphere are methane and carbon dioxide. State two...
• 09M.3.sl.TZ1.E1b: Discuss which two gases from the four gases in part (a) are the most significant for global warming.
• 09M.3.sl.TZ1.E1c: Discuss two effects of global warming.
• 09M.3.sl.TZ1.A1b: Explain what occurs at a molecular level during the absorption of infrared (IR) radiation by the...
• 11M.3.sl.TZ2.E1a: Identify two greenhouse gases not mentioned above. One of the gases that you identify should...
• 11M.3.sl.TZ2.E1b: The methane produced by sheep and cows can contribute to global warming. In Australia, it is...
• 11M.3.sl.TZ2.E1d: State one effect of global warming.
• 11M.3.sl.TZ2.E1c: The following graph shows the annual increase in the concentration of atmospheric carbon dioxide...
• 12M.3.sl.TZ1.E1a: Explain how the interaction of greenhouse gases in the atmosphere with radiation could lead to an...
• 12M.3.sl.TZ1.E1b: Suggest why carbon dioxide is the greenhouse gas most frequently connected with the effect of...
• 12M.3.sl.TZ1.E1c: Other than carbon dioxide and water, identify one other greenhouse gas and state its source.
• 11N.3.sl.TZ0.A2a: One type of molecular vibration that occurs when \({\text{C}}{{\text{O}}_{\text{2}}}\) molecules...
• 11N.3.sl.TZ0.E2a: Explain how this enhanced greenhouse effect causes the average temperature of the Earth to increase.
• 11N.3.sl.TZ0.E2b: Compare the contributions of carbon dioxide and methane to the enhanced greenhouse effect.
• 16M.3.sl.TZ0.12c: Scientists around the world conduct research into alternatives to fossil fuels. Suggest why...
• 16M.3.sl.TZ0.14: Atmospheric carbon dioxide and aqueous carbon dioxide in the oceans form a heterogeneous...
• 16M.3.sl.TZ0.15: Carbon dioxide, CO2, is a greenhouse gas. Outline, in molecular terms, how carbon dioxide...
• 16N.3.sl.TZ0.13a: Explain the effect of the increasing concentration of atmospheric carbon dioxide on the acidity...
• 16N.3.sl.TZ0.13b: (i) Describe the changes that occur at the molecular level when atmospheric carbon dioxide gas...
• 17M.3.sl.TZ1.17a: Suggest why it is only in recent years that specific predictions of the future effects of fossil...
• 17M.3.sl.TZ1.17b: Carbon dioxide has two different bond stretching modes illustrated below. Predict, with an...
• 17M.3.sl.TZ1.17c: Outline, giving the appropriate equation(s), how increasing levels of carbon dioxide will affect...
• 17M.3.sl.TZ1.17d: Many combustion processes also release particulate matter into the atmosphere. Suggest, giving...
• 17M.3.sl.TZ2.14a: Identify which region, A or B, corresponds to each type of radiation by completing the table.
• 17M.3.sl.TZ2.14b.i: Oceans can act as a carbon sink, removing some CO2(g) from the atmosphere. CO2(g)...
• 17M.3.sl.TZ2.14b.ii: Describe how large amounts of CO2 could reduce the pH of the ocean using an equation to support...
• 17N.3.sl.TZ0.13c: Climate change or global warming is a consequence of increased levels of carbon dioxide in the...
• 17N.3.sl.TZ0.13d: Outline how water and carbon dioxide absorb infrared radiation.
• 18M.3.sl.TZ1.9a: Identify one naturally occurring greenhouse gas, other than carbon dioxide or water vapour, and...
• 18M.3.sl.TZ1.9b: Formulate an equation that shows how aqueous carbon dioxide produces hydrogen ions, H+(aq).
• 18M.3.sl.TZ1.9c: The concentrations of oxygen and nitrogen in the atmosphere are much greater than those of...
• 18M.3.sl.TZ2.11a: Explain the molecular mechanism by which carbon dioxide acts as a greenhouse gas.
• 18M.3.sl.TZ2.11b: Discuss the significance of two greenhouse gases, other than carbon dioxide, in causing global...

C.6 Electrochemistry, rechargeable batteries and fuel cells (HL only)

• 14M.3.hl.TZ1.9a: State the energy change conversion involved in a fuel cell.
• 14M.3.hl.TZ1.9b: (i)     Identify the two half-equations that take place at the positive electrode (cathode) and...
• 14M.3.sl.TZ1.9a: State the energy change conversion involved in a fuel cell.
• 14M.3.sl.TZ1.9b: (i)     Identify the two half-equations that take place at the positive electrode (cathode) and...
• 14N.3.sl.TZ0.10: The diagrams below show a hydrogen-oxygen fuel cell with an alkaline electrolyte and a lead-acid...
• 13N.3.hl.TZ0.13a: State the equation, including state symbols, for the reaction that takes place when the cell is...
• 13N.3.hl.TZ0.13b: State the physical property of the products that allows this process to be reversed and the cell...
• 10N.3.sl.TZ0.C4a: State the half-equations for the reactions taking place at the negative electrode (anode) and the...
• 10N.3.sl.TZ0.C4b: A different type of cell has the half-equation...
• 10N.3.sl.TZ0.C4c: Both fuel cells and rechargeable batteries offer great potential for the future. Compare these...
• 10N.3.sl.TZ0.C4d: Suggest two problems associated with using hydrogen gas in a fuel cell.
• 09N.3.sl.TZ0.C4b: Identify a physical property of Cd(OH)2 which allows this process to be reversed and the battery...
• 09M.3.hl.TZ1.C2a: State the half-equations occurring at each electrode in the hydrogen-oxygen fuel cell in an...
• 09M.3.hl.TZ1.C2b: Describe the composition of the electrodes and state the overall cell equation of the...
• 09M.3.hl.TZ1.C2c: Compare a fuel cell and a lead-acid battery, with respect to possible concerns about pollution of...
• 09M.3.sl.TZ2.C3a: Describe how this is overcome in the lithium-ion battery.
• 09M.3.sl.TZ2.C3b: Describe the migration of ions taking place at the two electrodes in the lithium-ion battery when...
• 09M.3.sl.TZ2.C3c: Discuss one similarity and one difference between fuel cells and rechargeable...
• 12M.3.sl.TZ1.C2a: Compare fuel cells and rechargeable batteries giving one similarity and one...
• 12M.3.sl.TZ1.C2c: A common type of fuel cell uses hydrogen and oxygen with an acidic electrolyte. State the...
• 12M.3.sl.TZ1.C2d: The electrodes of fuel cells and rechargeable batteries have a feature in common with...
• 12M.3.hl.TZ2.C2c: Lead–acid batteries are heavy. Much lighter rechargeable cells are nickel–cadmium batteries used...
• 12M.3.sl.TZ2.C2a: A fuel cell can be made using an electrolyte of aqueous sodium hydroxide with porous electrodes...
• 12M.3.sl.TZ2.C2b: Electricity can also be generated from a lead–acid storage battery. The electrolyte is a solution...
• 12M.3.sl.TZ2.C2c: (i)     Explain why fuel cells are less damaging to the environment than nickel–cadmium...
• 11N.3.sl.TZ0.C3a: Describe the composition of the electrodes in a hydrogen-oxygen fuel cell.
• 11N.3.sl.TZ0.C3b: State the half-equation at each electrode in the hydrogen-oxygen alkaline cell. Positive...
• 16M.3.hl.TZ0.20a: One type of fuel cell contains a proton exchange membrane between electrodes and uses aqueous...
• 16M.3.hl.TZ0.20b: Suggest one advantage and one disadvantage of a fuel cell over a lead–acid battery as an energy...
• 16N.3.hl.TZ0.21a: The Geobacter species of bacteria can be used in microbial fuel cells to oxidise aqueous...
• 16N.3.hl.TZ0.21b: A concentration cell is an example of an electrochemical cell. (i) State the difference between...
• 17M.3.hl.TZ1.22a: Deduce half-equations for the reactions at the two electrodes and hence the equation for the...
• 17M.3.hl.TZ1.22b.i: Suggest a way in which they are similar.
• 17M.3.hl.TZ1.22b.ii: Outline the difference between primary and rechargeable cells.
• 17M.3.hl.TZ1.22c: Identify one factor that affects the voltage of a cell and a different factor that affects the...
• 17M.3.hl.TZ2.17c.i: Deduce the half-cell equations occurring at each electrode during discharge.
• 17M.3.hl.TZ2.17c.ii: Outline the function of the proton-exchange membrane (PEM) in the fuel cell.
• 17M.3.hl.TZ2.17c.iii: Explain how the flow of ions allows for the operation of the fuel cell.
• 17N.3.hl.TZ0.20a: Deduce the half-equations and the overall equation for the reactions taking place in a direct...
• 17N.3.hl.TZ0.20b: Outline one advantage and one disadvantage of the methanol cell (DMFC) compared with a...
• 18M.3.hl.TZ1.14a.i: Complete the half-equations on the diagram and identify the species moving between the electrodes.
• 18M.3.hl.TZ1.14a.ii: State the factor that limits the maximum current that can be drawn from this cell and how...
• 18M.3.hl.TZ2.13c: Fuel cells have a higher thermodynamic efficiency than octane. The following table gives some...

C.7 Nuclear fusion and nuclear fission (HL only)

• 17M.3.hl.TZ1.18b.ii: The mass of X is 8.005305 amu and that of \(_2^4{\text{He}}\) is 4.002603 amu. Determine the...
• 17M.3.hl.TZ2.16a.iii: Calculate the energy released, in MeV, in this reaction, using section 36 of the data booklet.
• 17N.3.hl.TZ0.18c.i: Calculate the loss in mass, in kg, and the energy released, in J, when 0.00100 mol of 228Ac...
• 17N.3.hl.TZ0.18c.ii: Determine the energy released, in J, by 0.00100 mol of 228Ac over the course of 18 hours.
• 17N.3.hl.TZ0.18d: Outline how nuclear ionising radiation can damage DNA and enzymes in living cells.
• 18M.3.hl.TZ1.14b.ii: Explain how the proportion of 235U in natural uranium is increased.
• 18M.3.hl.TZ2.16c.i: Calculate the relative rate of effusion of 235UF6(g) to 238UF6(g) using sections 1 and 6 of the...
• 18M.3.hl.TZ2.16c.ii: Explain, based on molecular structure and bonding, why diffusion or centrifuging can be used for...

C.8 Photovoltaic and dye-sensitized solar cells (HL only)

• 14M.3.hl.TZ2.4a: Explain which of the two structures would be coloured.
• 14M.3.hl.TZ2.4b: In terms of the wavelength of the visible light absorbed, suggest why the coloured form is blue.
• 14N.3.hl.TZ0.11: The photovoltaic cell is a valuable source of energy. Describe its construction and how it...
• 13N.3.hl.TZ0.13c: Pure silicon is a semiconductor but its conductivity can be increased when it is doped with small...
• 12N.3.hl.TZ0.A5c: One of the following organic compounds is colourless while the other is orange. Predict, with...
• 10M.3.hl.TZ2.A5: \(\beta \)-carotene is involved in the formation of vitamin A. Its sources include carrots,...
• 09M.3.hl.TZ1.C3c: Describe the use of silicon in photovoltaic cells. Include the following in your description: •...
• 11M.3.hl.TZ1.C5: Describe how silicon may be converted into a p-type semiconductor and explain why this leads to...
• 12M.3.hl.TZ2.A4b: Phenolphthalein indicator is colourless in solutions with a pH less than 8.2 but pink in...
• 16M.3.hl.TZ0.21a: State how n-type and p-type doping of silicon is achieved and the nature of electric charge...
• 16M.3.hl.TZ0.21b: In dye-sensitized solar cells (DSSCs), nanoparticles coated with a black dye are trapped between...
• 16N.3.hl.TZ0.21c: Dye-sensitized solar cells (DSSC) convert solar energy into electrical energy. (i) Describe how...
• 17M.3.hl.TZ1.19a: Identify two ways in which the structure of the dye shown resembles the chlorophyll molecule. Use...
• 17M.3.hl.TZ1.19b: Both photosynthesis and the Grätzel cell use energy from sunlight to bring about reduction....
• 17M.3.hl.TZ2.18a.ii: The structures of 11-cis-retinal and β-carotene are given in section 35 of the data booklet....
• 17M.3.hl.TZ2.19a: Contrast how absorption of photons and charge separation occur in each device.
• 17M.3.hl.TZ2.19b: Suggest one advantage a DSSC has over a silicon based photovoltaic cell.
• 17N.3.hl.TZ0.19b: The natural absorption of light by chlorophyll has been copied by those developing dye-sensitized...
• 18M.3.hl.TZ1.15a: Early photovoltaic cells were based on silicon containing traces of other elements. State the...
• 18M.3.hl.TZ1.15b: Dye-sensitized solar cells, DSSCs, use a dye to absorb the sunlight. State two advantages that...
• 18M.3.hl.TZ1.15c: The structure of two dyes used in DSSCs are shown. Predict, giving a reason, which dye will...
• 18M.3.hl.TZ2.18a: Draw the Lewis (electron dot) structure for an appropriate doping element in the box in the...
• 18M.3.hl.TZ2.18b.i: State the feature of the molecules responsible for the absorption of light.
• 18M.3.hl.TZ2.18b.ii: Outline why complex B absorbs light of longer wavelength than complex A.