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प्रश्न
Although carbon and hydrogen are better reducing agents but they are not used to reduce metallic oxides at high temperatures. Why?
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उत्तर
It is because at high temperature carbon and hydrogen react with metals to form carbides and hydrides respectively.
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संबंधित प्रश्न
The process of leaching alumina, using sodium carbonate is called
- Bayer's process
- Decomposition
- Cyanide process
- Hall's process
What is the chemical composition of malachite?
- CuO . CuC03
- Cu(OH)2 CuC03
- CuO.Cu(OH)2
- Cu2O . Cu(OH)2
Silica is added to roasted copper ore during smelting process to remove _______.
(A) ferrous sulphide
(B) ferrous oxide
(C) cuprous sulphide
(D) cuprous oxide
Out of C and CO, which is a better reducing agent at the lower temperature range in the blast furnace to extract iron from the oxide ore?
Fe2O3 is reduced to spongy iron near the top of blast furance by
(A) H2
(B) CaO
(C) SiO2
(D) CO
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Indicate the principle behind the method used for the refining of zinc.
Explain the following methods to protect metals from corrosion:
Passivation
Draw a neat, well labelled diagram of electrolytic cell for extraction of aluminium
Why does copper obtained in the extraction from copper pyrites have a blistered appearance?
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]
Bauxite has the composition
Give the uses of zinc.
Which among the following statement is correct?
When copper ore is mixed with silica, in a reverberatory furnace copper matte is produced. The copper matte contains ______.
Which of the following options are correct?
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(ii) In extraction of silver, silver is extracted as cationic complex.
(iii) Nickel is purified by zone refining.
(iv) Zr and Ti are purified by van Arkel method.
Write the chemical reactions involved in the extraction of gold by cyanide process. Also give the role of zinc in the extraction.
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