What is an electrode

Back to: PRIMARY SEVEN P7 SCIENCE TOPICAL QUESTIONS AND ANSWERS

What is an electrode?

• An electrode is a piece of metal which allows electric current to enter and leave a cell when dipped in an electrolyte. Or
• An electrode is a piece of metal that conducts electricity.
  Qn. What is an electrolyte?
• An electrolyte is a liquid that conducts electricity.
  Qn. Give examples of electrolytes.
• Lemon juice
• Urine
• Undistilled water
• Salt solution
• Dilute sulphuric acid
• Dilute hydrochloric acid
  The structure of a wet / simple cell

The structure of a wet / simple cell

Qn. Identify the form of energy stored in a wet cell.

• Chemical energy
  Note
  Chemical energy stored in a wet cell is converted to electric energy.
  The structure of a home made wet cell.

Qn. State the factors that affect the efficiency of a wet / simple cell.

• Polarization
• Local action
  Qn. What is polarization?
• Polarization is the formation of hydrogen gas bubbles on a copper plate of a simple cell.
  Note:
• When hydrogen bubbles cover the copper plate, they reduce the
  e.m.f of the cell and the bulb will stop giving light.