Chemical cells and fuel cells (chemistry only) key terms

cell

A device that contains chemicals which react to produce electricity. In Cells and batteries, this term is used specifically to support the learning objective: (chemistry only) Describe that cells contain chemicals that react to produce electricity.

electrolyte

A substance that conducts electricity when dissolved in water or melted, allowing the flow of ions.

Voltage

The measure of the electric potential difference produced by a cell, influenced by factors such as electrode type and electrolyte.

Electrode

A conductor through which electricity enters or leaves a cell, playing a crucial role in the electrochemical reactions that generate voltage.

simple cell

A simple cell consists of two different metals in contact with an electrolyte, generating electricity through electrochemical reactions.

electrolyte

An electrolyte is a substance that conducts electricity when dissolved in water or molten, allowing ions to move and participate in electrochemical reactions.

electrode

A conductor through which electricity enters or leaves a cell. In Cells and batteries, this term is used specifically to support the learning objective: (chemistry only) Explain why two different electrodes are needed in a simple chemical cell.

chemical cell

A device that converts chemical energy into electrical energy through electrochemical reactions.

battery

A device consisting of two or more cells connected together in series to produce electricity.

series connection

A configuration where multiple cells are connected in a sequence, increasing the total voltage output.

series connection

A method of connecting multiple cells where the positive terminal of one cell is connected to the negative terminal of the next, increasing the total voltage output.

voltage

The measure of electric potential difference between two points, which determines the amount of energy provided by a cell or battery.

Non‑rechargeable cell

A simple electrochemical cell in which the chemical reaction proceeds in one direction and stops when one reactant is depleted, making the cell unable to be recharged.

Reactant depletion

The consumption of a reactant to the point where it is no longer available to continue the electrochemical reaction, causing the cell to cease producing electricity.

Alkaline batteries

A type of non-rechargeable battery that uses an alkaline electrolyte. In Cells and batteries, this term is used specifically to support the learning objective: (chemistry only) Identify alkaline batteries as non-rechargeable.

Non-rechargeable cell

A cell that cannot be recharged once its reactants are used up. In Cells and batteries, this term is used specifically to support the learning objective: (chemistry only) Identify alkaline batteries as non-rechargeable.

Rechargeable cell

A cell whose electrochemical reaction can be reversed by applying an external electrical current, allowing it to be recharged and used repeatedly.

External electrical current

An externally applied flow of electrons that drives the reverse of the cell’s spontaneous reaction, restoring the original reactants and enabling the cell to be reused.

reactivity series

A list of metals arranged in order of decreasing reactivity. In Cells and batteries, this term is used specifically to support the learning objective: (chemistry only) Interpret data for relative reactivity of different metals in cells.

electrochemical reaction

A chemical reaction that involves the transfer of electrons, producing electricity.

voltage

The measure of the electric potential difference produced by a cell. In Cells and batteries, this term is used specifically to support the learning objective: (chemistry only) Evaluate the use of cells from information about voltage, electrode materials, electrolyte and rechargeability.

electrode

A conductor through which electricity enters or leaves a cell. In Cells and batteries, this term is used specifically to support the learning objective: (chemistry only) Evaluate the use of cells from information about voltage, electrode materials, electrolyte and rechargeability.

cell

A device that converts chemical energy into electrical energy through electrochemical reactions.

electrolyte

A substance that conducts electricity when dissolved in water or molten, allowing ions to move and facilitate electrochemical reactions.

fuel cell

A device that converts chemical energy from a fuel and an oxidant into electricity through electrochemical reactions.

oxidation

A chemical reaction in which a substance loses electrons, often associated with the reaction of a fuel in a fuel cell.

Fuel cell

An electrochemical device that generates electricity by oxidising a fuel, such as hydrogen, using an external source of oxygen or air.

Hydrogen fuel cell

A type of fuel cell that uses hydrogen gas as the fuel, oxidising it at the anode to produce electricity, water, and heat.

fuel cell

A device that converts chemical energy from a fuel into electricity through electrochemical reactions.

oxidation

A chemical process in which a substance loses electrons, often associated with the reaction of a fuel in a fuel cell.

fuel cell

A device that converts chemical energy from a fuel into electrical energy through electrochemical reactions.

potential difference

The difference in electric potential between two points in a circuit, which drives the flow of electric current.

Overall reaction

The complete chemical change that occurs in a hydrogen fuel cell, where hydrogen gas is oxidised at the anode to produce water at the cathode.

Oxidation of hydrogen

The loss of electrons by hydrogen atoms in the fuel cell, forming protons that combine with oxygen to generate water.

hydrogen fuel cell

A device that converts chemical energy from hydrogen and oxygen into electrical energy through electrochemical reactions.

rechargeable cell

A type of cell that can be recharged by reversing the chemical reactions that occur during discharge.

Hydrogen fuel cell

An electrochemical device that generates electricity by oxidising hydrogen gas at the anode and reducing oxygen at the cathode, producing water as the sole product.

Rechargeable battery

A type of electrochemical cell whose chemical reactions can be reversed by applying an external electric current, allowing the cell to be recharged and reused.

Fuel supply

The source of energy that is fed into a fuel cell, typically hydrogen gas or another combustible fuel, which is oxidised to generate electricity.

Rechargeability

The ability of a cell or battery to have its chemical reactions reversed by an external electrical current, allowing it to be used repeatedly.

Hydrogen electrode

The electrode in a hydrogen fuel cell where hydrogen gas is oxidised to protons and electrons.

Half‑cell reaction

The balanced chemical equation that describes the oxidation or reduction occurring at one electrode in an electrochemical cell.

half equation

An equation that shows the reduction or oxidation process occurring at an electrode in an electrochemical cell.

hydrogen fuel cell

A device that converts chemical energy from hydrogen and oxygen into electrical energy through electrochemical reactions.

hydrogen fuel cell

A device that converts chemical energy from hydrogen and oxygen into electrical energy, producing water as a byproduct.

half equation

An equation that shows the oxidation or reduction process occurring at an electrode during an electrochemical reaction.