Galvanic corrosion is caused by contact between two unlike metals.

Galvanic corrosion is caused by contact between two unlike metals.

• A. True
• B. False
• C. Only in water
• D. Only when heated

Answer: (A)

Galvanic corrosion occurs when two different metals are in electrical contact in the presence of an electrolyte. When metals with different electrode potentials meet, electrons flow from the more active metal to the less active metal through the metal connection, while ions move in the electrolyte to complete the circuit. This makes the more anodic metal oxidize and corrode, while the cathodic metal is relatively protected. The electrolyte—often moisture or salt-containing water—enables this transfer; without an electrolyte, mere contact won’t drive significant corrosion. So, the statement is true: contact between two unlike metals is the key initiating factor, with the environment (electrolyte) enabling the reaction. It’s not limited to water or to heating, though moisture and higher temperatures can speed things up.

Galvanic corrosion occurs when two different metals are in electrical contact in the presence of an electrolyte. When metals with different electrode potentials meet, electrons flow from the more active metal to the less active metal through the metal connection, while ions move in the electrolyte to complete the circuit. This makes the more anodic metal oxidize and corrode, while the cathodic metal is relatively protected. The electrolyte—often moisture or salt-containing water—enables this transfer; without an electrolyte, mere contact won’t drive significant corrosion. So, the statement is true: contact between two unlike metals is the key initiating factor, with the environment (electrolyte) enabling the reaction. It’s not limited to water or to heating, though moisture and higher temperatures can speed things up.