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प्रश्न
Explain the following methods to protect metals from corrosion:
Galvanization
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उत्तर
Galvanization:
1) The rusting of iron can be prevented by coating the metal surface with another metal such as zinc, that is oxidized in preference to iron. This process is called galvanization.
2) If the zinc layer is scratched, even then it protects iron from corrosion as long as Fe and Zn are in contact. If Fe is oxidized to Fe2+, then Zn immediately reduces Fe2+ back to Fe.
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संबंधित प्रश्न
Write the names and chemical formulae of any one ore of iron.
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- Bayer's process
- Decomposition
- Cyanide process
- Hall's process
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- CuO . CuC03
- Cu(OH)2 CuC03
- CuO.Cu(OH)2
- Cu2O . Cu(OH)2
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(A) ferrous sulphide
(B) ferrous oxide
(C) cuprous sulphide
(D) cuprous oxide
Write chemical formulae of the following ores :
(a) Calamine
(b) Haematite
(c) Magnetite
(d) Corundum
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(A) H2
(B) CaO
(C) SiO2
(D) CO
Draw neat and labelled diagram of Bessermer converter used in the extraction of copper.
What is the role of cryolite in the extraction of aluminium?
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What happens when a nickel rod is dipped into a copper sulphate solution? Justify your answer.
[\[\ce{E{^{\circ}_{Ni^{+2}/Ni}}}\] = − 0.25 V and \[\ce{E{^{\circ}_{Cu^{+2}/Cu}}}\] = +0.34 V]
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Metals which occur in their native state in nature:
Metal which is found in free state is:
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The sulphide ore of iron is ____________.
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The important ore of iron is:-
When compared to ΔG° for the formation of Al2O3 ΔG° for the formation of Cr2O3 is
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