In a system where two dissimilar metals are in contact with moisture, the electrochemical reaction that accelerates deterioration is known as ___.

In a system where two dissimilar metals are in contact with moisture, the electrochemical reaction that accelerates deterioration is known as ___.

• A. Oxidation
• B. Corrosion
• C. Cathodic reaction
• D. Electrolysis

Answer: (D)

When two dissimilar metals are in contact in the presence of moisture, a tiny galvanic cell forms where the electrolyte (the moisture) lets ions move. The more active metal becomes the anode and oxidizes, while the other metal acts as the cathode and undergoes reduction. This spontaneous electrochemical reaction speeds up the deterioration of the metals—the process we call corrosion, specifically galvanic corrosion. Electrolysis would require an external energy source and isn’t what’s driving the damage here, and oxidation or a cathodic reaction alone don’t describe the overall deterioration.

When two dissimilar metals are in contact in the presence of moisture, a tiny galvanic cell forms where the electrolyte (the moisture) lets ions move. The more active metal becomes the anode and oxidizes, while the other metal acts as the cathode and undergoes reduction. This spontaneous electrochemical reaction speeds up the deterioration of the metals—the process we call corrosion, specifically galvanic corrosion. Electrolysis would require an external energy source and isn’t what’s driving the damage here, and oxidation or a cathodic reaction alone don’t describe the overall deterioration.