International General Certificate of Secondary Education (IGCSE) Chemistry Practice Exam

What is the charge of the anode?

1. Negative

2. Neutral

3. Positive

4. Varies depending on the substance

The correct answer is: Positive

In electrochemical cells, the anode is the electrode where oxidation occurs, and it is always positively charged during the electrochemical reaction. This is because, in the process of oxidation, electrons are released from the substance at the anode and flow towards the cathode, which is negatively charged. The movement of positive ions toward the anode and the flow of electrons away create a positive charge at the anode. This concept is critical in understanding how batteries and electrolysis work; during discharge, for example, the anode attracts negative ions from the electrolyte, further emphasizing its positive charge. Options suggesting the anode is negative or neutral do not align with these fundamental principles of electrochemistry. Additionally, while the charge may vary under different conditions or specific cell configurations, the standard anode charge remains positive.