1. Which one of the following statements is correct?
A. Fuel cells and galvanic cells produce heat.
B. Fuel cells have inert electrodes whereas galvanic cells do not.
C. Fuel cells have porous electrodes whereas galvanic cells do not.
D. Fuel cells and galvanic cells operate when electrons flow through the electrolyte.

Solution
2. Consider two types of drone: petrol-powered and hydrogen-fuel-cell powered.
Which one of the following statements is correct about petrol-powered drones and hydrogen-fuel-cell powered drones?
A. They both produce greenhouse gases.
B. Only petrol-powered drones produce heat.
C. They both have the same energy transformations.
D. The overall reactions in hydrogen-fuel-cell powered drones are endothermic.
Solution
3. Methane, CH₄ , and methanol, CH₃OH, can both be used to power fuel cells.
Methane and methanol fuel cells produce
A. the same amount of greenhouse gases and the same number of electrons per mol of fuel reacted.
B. the same amount of greenhouse gases and a different number of electrons per mol of fuel reacted.
C. a different amount of greenhouse gases and the same number of electrons per mol of fuel reacted.
D. a different amount of greenhouse gases and a different number of electrons per mol of fuel reacted.

Solution

4. Scientists are investigating the possibility of using coconut oil with an aqueous electrolyte of potassium hydroxide, KOH(aq), to power a fuel cell.
i. Write the half-equation that would occur at the cathode of a coconut oil fuel cell in an alkaline electrolyte. 1 mark

Solution

ii. State one design feature of the cathode that helps the fuel cell operate efficiently. 1 mark

Solution

5. State one reason why it may be better to obtain energy from coconut oil using a fuel cell rather than direct combustion. 1 mark

Solution

6. Give one reason why coconut oil may not be a practical fuel for a fuel cell. Do not refer to environmental issues or sustainability in your answer. 2 marks

Solution