Galvanized iron sheets are coated withA. `Cr`B. `Zn`C. `Ni`D. `Cu`

1.	Galvanized iron sheets are coated withA. `Cr`B. `Zn`C. `Ni`D. `Cu`
Answer» Correct Answer - B Galvanized iron is sheet iron coated with a layer of `Zn` to prevent corrosion, usually made by dipping the sheet `Al` added to prevent the formation of a brittle `Zn-Fe` alloy, Thus, galvanized iron is sometimes called Zinc-plated iron. Zinc is more easily oxidized than iron: `Zn(s) rarr Zn^(2+)(aq.)+2e^(-) E^(@) = +0.76V` So even if a scratch exposes the iron, the `Zn` is still attacked In this case, the `Zn` metal scrves as the anode and the iron is the cathode.

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Galvanized iron sheets are coated withA. `Cr`B. `Zn`C. `Ni`D. `Cu`

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