In a conductivity apparatus, like the one above, you should never touch the electrodes while the power is on. Which part should you avoid touching to ensure safety?

• A. Solution container
• B. Electrodes
• C. Plastic casing
• D. Power cord insulation

Answer: (B)

Verified step by step guidance

1. Understand the function of each part of the conductivity apparatus: the electrodes are the conductive parts that come into contact with the solution to measure its conductivity.
2. Recognize that touching the electrodes while the power is on can cause an electric shock because they are connected to the electrical circuit.
3. Identify that the plastic casing is an insulating material designed to protect the user from electrical components, so touching it is generally safe.
4. Note that the power cord insulation is also designed to prevent electrical shock by covering the wires, so it should not be damaged but touching the intact insulation is safe.
5. Conclude that to ensure safety, you should avoid touching the electrodes when the power is on, as they are the parts that carry current directly.