What is stored by a dry Leclanhé cell?

Step 1: Analyze the question The question asks what form of energy is stored in a dry Leclanché cell. This is a primary cell, commonly found in torches, radios and other small devices.

Step 2: Explain the concept A cell is a device that converts stored chemical energy into electrical energy. A dry Leclanché cell has these parts:

• Positive electrode: a carbon rod surrounded by manganese(IV) oxide (MnO₂), which acts as a depolarizer.
• Negative electrode: a zinc case.
• Electrolyte: a moist paste of ammonium chloride (NH₄Cl).

The zinc reacts chemically with the electrolyte. This reaction releases electrons, which flow through the external circuit as electric current.

Step 3: Eliminate the options

• B. Heat energy: The cell does not store heat. Some heat may be produced when current flows, but it is not what is stored.
• C. Mechanical energy: This is energy of motion or position. A cell has no moving parts storing energy.
• D. Nuclear energy: This comes from atomic nuclei, as in reactors. It has nothing to do with a Leclanché cell.
• E. Solar energy: This comes from sunlight, as in solar cells.
• A. Chemical energy: The energy is held in the chemical substances (zinc and manganese dioxide) and released through chemical reaction. This is correct.

Step 4: Answer

Exam tip: Remember that cells and batteries store chemical energy, and they convert it to electrical energy when in use. A quick way to recall it is "Cell = Chemical."