Subjects · Leaving Cert Chemistry
Leaving Cert Chemistry: Electrochemistry
How often Electrochemistry comes up on the Chemistry papers, every year it was asked, and questions to try.
HL Asked on 5 of the last 10 Higher Level papers, most recently in 2026.
OL Asked on 6 of the last 10 Ordinary Level papers, most recently in 2025. most years
June 2027 is the first exam on the new Chemistry course. These come from the 2016–2026 papers, so read them as a guide.
Quick ones on Electrochemistry.
- Oxygen gas
- Chlorine gas
- Sodium metal
- Nothing chemical happens there
- Reduction, the gain of electrons
- Oxidation, the loss of electrons
- Zinc
- Both are negative
- Copper
Show the answers
(a) Chlorine gas
(b) Oxidation, the loss of electrons
(c) Zinc
Higher Level
Asked on 5 of the last 10 Higher Level papers, most recently in 2026.
Every paper, year by year
| Year | Where it came up |
|---|---|
| 2026 | Q4(j) |
| 2025 | Not asked |
| 2024 | Q4(i) |
| 2023 | Q11(b) |
| 2022 | Q4(i) |
| 2021 | Not asked |
| 2019 | Q4(f) |
| 2018 | Not asked |
| 2017 | Not asked |
| 2016 | Not asked |
Links open the State Examinations Commission’s paper for that year.
More Electrochemistry questions
Electrochemistry, 2 marks
What is an electrolyte?
- Any substance at all that conducts electricity, whether solid, liquid or in solution
- A metal that conducts electricity when solid and is not changed by the current
- A substance that conducts electricity when molten or in solution and is decomposed by it
Show the answer
A substance that conducts electricity when molten or in solution and is decomposed by it
Conduction is by moving ions, not free electrons, which is why a metal wire is a conductor but not an electrolyte.
Electrochemistry, 2 marks
How does a fuel cell differ from an ordinary chemical cell?
- It stores all its reactants inside until they run out
- It needs a constant supply of fuel and oxidising agent from outside
- It can never produce electricity without being recharged
Show the answer
It needs a constant supply of fuel and oxidising agent from outside
In a hydrogen fuel cell, hydrogen and oxygen are fed in and water is removed, so it runs as long as fuel is supplied.
Electrochemistry, 2 marks
Why is hydrogen made by electrolysis using wind power called a sustainable fuel?
- No fossil fuel is burned, so no CO2 is released making or using it
- It gives out more energy when burned than the electrolysis takes in
- Hydrogen is found free in large amounts in the air
Show the answer
No fossil fuel is burned, so no CO2 is released making or using it
Burning hydrogen or using it in a fuel cell gives only water. The electricity for the electrolysis must also come from renewable sources.
Ordinary Level
Asked on 6 of the last 10 Ordinary Level papers, most recently in 2025. most years
Every paper, year by year
| Year | Where it came up |
|---|---|
| 2026 | Not asked |
| 2025 | Q9 |
| 2024 | Not asked |
| 2023 | Q10(b) |
| 2022 | Q9 |
| 2021 | Q10(b) |
| 2019 | Not asked |
| 2018 | Q4(c) |
| 2017 | Q4(j) |
| 2016 | Not asked |
Links open the State Examinations Commission’s paper for that year.
More Electrochemistry questions
Electrochemistry, 2 marks
When an object is electroplated with copper, the object is made the?
- Anode
- Electrolyte
- Cathode
Show the answer
Cathode
Copper ions are positive, so they move to the negative cathode and form a coat of copper metal on it.
Electrochemistry, 2 marks
Which of these metals is highest in the electrochemical series (most reactive)?
- Silver
- Potassium
- Copper
Show the answer
Potassium
Potassium loses electrons most easily. Copper and silver are near the bottom and are unreactive.
Electrochemistry, 2 marks
Gas formed at the cathode in the electrolysis of water, with sodium sulfate added?
- Hydrogen
- Oxygen
- Chlorine
Show the answer
Hydrogen
Hydrogen forms at the negative cathode and oxygen at the positive anode, in a 2 to 1 ratio by volume.
Other Chemistry topics
- Acids and bases
- Atomic structure
- Chemical equilibrium
- Concentration
- Covalent bonding
- Electronegativity
- Fuels and heats of reaction
- Functional groups
- Gas laws
- Hydrocarbons
- Mandatory experiments
- Organic reactions
- Oxidation and reduction
- pH
- Rates of reaction
- Shapes of molecules
- The mole
- The periodic table
- Trends
- Volumetric analysis
- Water treatment
- Electron configuration
- Formulas and equations
- Organic synthesis
- Radioactivity
- Instrumentation and separation
- Ionic bonding
- Intermolecular forces
- Environmental chemistry
- Isomerism
- Industrial chemistry
- Lab safety
- States of matter