Identify the correct statement :
Show Hint
- Iron corrodes in oxygen-free water.
- Iron corrodes more rapidly in salt water because its electrochemical potential is higher.
- Corrosion of iron can be minimized by forming a contact with another metal with a higher reduction potential.
- Corrosion of iron can be minimized by forming an impermeable barrier at its surface.
The Correct Option is D
Solution and Explanation
(2) Salt water increases the conductivity of the electrolyte; it is not because the electrochemical potential is higher - false.
(3) Sacrificial protection needs a metal with a lower reduction potential (e.g. Zn, Mg); a higher one would make iron the anode and speed up corrosion - false.
(4) A paint, oil, tin or other impermeable coating keeps out O2 and moisture - true.
Answer: (4) Corrosion of iron can be minimized by forming an impermeable barrier at its surface.
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