Question

Identify the incorrect statement about the corrosion

• A. In the composition type of galvanic cell, metal with lower standard reduction potential undergoes corrosion
• B. In stress cell type of galvanic cell, corrosion occurs at the stressed area of the metal
• C. The rate of corrosion is more, when the area of cathode is smaller
• D. In concentration cell type of galvanic cell, the metal below the water level undergoes corrosion readily

Hint:

Remember: Small Anode + Big Cathode = Rapid Corrosion. The "sink" (cathode) is bigger than the "source" (anode).

Answer 1

The Correct Option is C

Step 1: Concept Corrosion rates are heavily influenced by the relative surface areas of the anode and cathode.

Step 2: Meaning According to the "Small Anode, Large Cathode" rule, corrosion is accelerated if the anode is small relative to the cathode.

Step 3: Analysis If the cathode area is large, it can consume electrons faster, forcing the smaller anode to dissolve (corrode) much more rapidly. Conversely, a smaller cathode area relative to the anode actually decreases the corrosion rate.

Step 4: Conclusion Statement (C) is incorrect because a smaller cathode area generally leads to a lower rate of corrosion, not more.
Final Answer: (C)