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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.
What is the chemical composition of malachite?
- CuO . CuC03
- Cu(OH)2 CuC03
- CuO.Cu(OH)2
- Cu2O . Cu(OH)2
Write the reactions involved in the zone of reduction in blast furnace during extraction of iron.
Fe2O3 is reduced to spongy iron near the top of blast furance by
(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 limestone in the extraction of iron from its oxides?
Indicate the principle behind the method used for the refining of zinc.
What is the role of silica in the extraction of copper?
Which form of the iron is the purest form of commercial iron?
Describe the roles of the following: SiO2 in the extraction of copper from copper matte
Which of the ores mentioned can be concentrated by magnetic separation method?
Differentiate between “minerals” and “ores”.
Which among the following minerals does NOT contain aluminium?
(a) Cryolite
(b) Siderite
(c) China clay
(d) Corundum
Why does copper obtained in the extraction from copper pyrites have a blistered appearance?
What is the role of the following compound-
SiO2 in the extraction of copper from copper pyrites?
Metal which is found in free state is:
Identify a mineral for the major source of boron from the following list?
The important ore of iron is:-
In the electrolytic process for the extraction of aluminium the electrolyte is:-
Which of the following is not ore of aluminium?
In the extraction of iron, the slag produce is
Which of the following statements, about the advantage of roasting of sulphide ore before reduction is not true?
Match List - I with List - II.
| List - I | List - II | ||
| (One) | (Composition) | ||
| (A) | Siderite | (I) | FeCO3 |
| (B) | Malachite | (II) | CuCO3 · Cu(OH)2 |
| (C) | Sphalerite | (III) | ZnS |
| (D) | Calamine | (IV) | ZnCO3 |
Choose the correct answer from the options given below:
