Bare metal, moisture (electrolyte) and ___ are needed for corrosion to occur.

Bare metal, moisture (electrolyte) and ___ are needed for corrosion to occur.

• A. Oxygen
• B. Nitrogen
• C. Hydrogen
• D. Carbon dioxide

Answer: (A)

Corrosion requires three things: bare metal, moisture that acts as the electrolyte, and an oxidizing agent. The oxidizing agent is typically oxygen from the air, which dissolved in the moisture and accepts electrons from the metal. This electron transfer forms metal oxide, i.e., rust on iron or steel. The moisture lets ions move, enabling the electrochemical reactions, while the bare metal provides the electrons to be released. Nitrogen and hydrogen don’t serve as the oxidizing agent in this scenario, and carbon dioxide isn’t the necessary oxidant either (although it can influence acidity...). Oxygen is the key component that drives the corrosion process in the presence of moisture.

Corrosion requires three things: bare metal, moisture that acts as the electrolyte, and an oxidizing agent. The oxidizing agent is typically oxygen from the air, which dissolved in the moisture and accepts electrons from the metal. This electron transfer forms metal oxide, i.e., rust on iron or steel. The moisture lets ions move, enabling the electrochemical reactions, while the bare metal provides the electrons to be released.

Nitrogen and hydrogen don’t serve as the oxidizing agent in this scenario, and carbon dioxide isn’t the necessary oxidant either (although it can influence acidity...). Oxygen is the key component that drives the corrosion process in the presence of moisture.