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Question
Zinc can be coated on iron to produce galvanized iron but the reverse is not possible. It is because ____________.
Options
Zinc is lighter than iron
Zinc has lower melting point than iron
Zinc has lower negative electrode potential than iron
Zinc has higher negative electrode potential than iron
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Solution
Zinc can be coated on iron to produce galvanized iron but the reverse is not possible. It is because Zinc has higher negative electrode potential than iron.
Explanation:
`"E"_("Zn"^(2+)|"Zn")^0` = – 0.76 V and `"E"_("Fe"^(2+)|"Fe")^0` = 0.44 V
Zinc has higher negative electrode potential than iron, iron cannot be coated on zinc.
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